1. SCOPE ……………………………………………………………………………………
2. REFERENCES ……………………………………………………………………………………
3. DEFINITIONS ……………………………………………………………………………………
4. GENERAL REQUIREMENTS ……………………………………………………….
4.1 Documentations ……………………………………………………….
5. DEVIATIONS FROM SPECIFICATION ……………………………………………………….
6. SITE CONDITIONS ……………………………………………………….
6.1 Outdoor ……………………………………………………………………………………
6.2 Indoor ……………………………………………………………………………………
7. TRANSFORMER RECTIFIER (TR) ……………………………………………………….
7.1 General ……………………………………………………………………………………
7.2 Design Life ……………………………………………………….
7.3 Design and Construction – Mechanical …………………………..
7.4 Design and Construction – Electrical: …………………………..
8. REMOTE MONITORING SYSTEM (RMS) …………………………..
8.1 General ……………………………………………………………………………………
9. QUALITY CONTROL & TESTS: ……………………………………………………….
9.1 General ……………………………………………………………………………………
10. RECOMMENDED SPARE PARTS ……………………………………………………….
11. OPERATING INSTRUCTIONS & MAINTENANCE HANDBOOK
11.1 General ……………………………………………………………………………………
12. TR SHIPPING ……………………………………………………….
1. Scope
This Specification covers the minimum requirements for a Transformer Rectifier (TR) and Remote
Monitoring System for Cathodic Protection Systems in all SABIC plants. This standard shall be
read in conjunction with SABIC Engineering Standard (SES) L02-E01 and L02-E02.
2. References
Reference is made in this standard to the following documents. The latest issues, amendments,
and supplements to these documents shall apply unless otherwise indicated.
SABIC Engineering Standard (SES)
E02-G01 Electrical System Design Criteria
E02-E02 Hazardous Area Classification
L02-E01 Cathodic Protection of Plant Facilities
L02-E02 Cathodic Protection of Steel in Concrete
L02-M01 Commissioning and Operation of Cathodic Protection systems of Plant Facility Structures
Z01-G04 Measurement Units for use in SABIC Projects
American Welding Society (AWS)
D1-1 Structural Welding Code (AWS)
American National Standard Institute (ANSI)
B2.1 Standard for Pipe Thread
C34.2 Practices and Requirements for Semiconductor Power Rectifiers
Institute of Electrical Electronic Engineering (IEEE)
C57.18.10 Standard Practices and Requirements for Semiconductor Power Rectifier Transformers.
Insulated Cable Engineers Association (ICEA)
S61-402 Thermoplastic Insulated Wire and Cable
National Electrical Manufacturer’s Association (NEMA)
ICS 6 Enclosures for Industrial Controls and Systems
250 Enclosures for electrical equipment
National Fire Protection Association (NFPA)
70 National Electrical Code (NEC)
Swedish Painting StandardSIS-05-5900 Swedish Pictorial Surface Preparation Standards for
Painting Steel Surfaces.
Underwriters Laboratories, Inc.
83 Thermoplastic-insulated Wires and Cables
3. Definitions
For the purpose of understanding this specification, the following definitions apply.
Alternating Current (AC). Is an electric current whose direction reverses cyclically.
Constant Current Control. Mode of operation of a transformer rectifier to provide constant
current output. In this operation mode, drive voltage automatically adjusts with changes in the
circuit resistance to provide constant current.
Constant Voltage Control. Mode of operation of a transformer rectifier to provide constant
voltage output. In this operation mode, current automatically adjusts with changes in the circuit
resistance to provide constant voltage.
Constant Potential Control. Mode of operation of a transformer rectifier to provide constant
structure potential with respect to reference cell. In this operation mode, current & voltage
automatically adjusts with changes in the circuit resistance to provide constant potential.
Embedded Reference Electrode. A reference electrode which is permanently fixed within the
electrolyte close to the metallic structure but not touching it.
Junction Box (JB). An electrical junction box is a container for electrical junctions.
Silicon-Controlled Rectifier (SCR) (or Semiconductor-Controlled Rectifier) is a four-layer solid
state device that controls current.
Interrupter. A timing device that permits a cyclic off/on interruption to the flow of cathodic
protection current.
Metal Oxide Varistor (MOV) a device that often used to protect circuits against excessive transient
voltage.
Transformer Rectifier (TR). A device used to convert alternating current (ac) to direct current
(dc). In a CP system, the transformer rectifier is used to control the voltage, current or potential.
4. General Requirements
a. All electrical equipment and components within the system shall be tested by a certified testing
laboratory, such as UL and carry the Laboratory‟s label.
b. Each manufacturer and vendor shall meet the requirement of this specification.
c. TR unit shall be supplied only by SABIC approved and pre-qualified manufacturers.
d. The warrant period for each TR shall be five (5) years including hardware and software.
e. The TR unit shall be assembled at the manufacturer‟s workshops as complete as practical with
respect to shipment and handling.
4.1 Documentations
4.1.1 Each TR shall be supplied with an operation and maintenance manual. The manual shall
explain step by step operation instruction and troubleshooting. The Operation and
Maintenance manual cover shall be waterproof type.
4.1.2 Operation and maintenance manual shall include a list of all TR spare parts with their
specifications.
4.1.3 Documents shall be provided in units conforming to SES Z01-G04, and shall be written in
English language.
4.1.4 A complete line (schematic) circuit diagram showing the actual factory wiring for all
components shall be mounted inside each TR. The schematic shall be printed in a neat and
legible drafting manner.
4.1.5 Detail design of the TR unit shall be provided by the manufacturer. The manufacturer shall
ensure the TR units are sized and oriented to allow clear access to the units.
4.1.6 The manufacturer shall submit a dimensioned general arrangement drawing , a component
layout drawing , a circuit diagram and a testing schedule, for SABIC review and approval.
4.1.7 All necessary fixings for mounting the TR unit shall be provided. All fixings shall be corrosion
protected.
5. Deviations from Specification
Any conflict(s) between this specification, SES and industry standards, engineering drawings, and
contract documents shall be resolved at the discretion of SABIC.
6. Site Conditions
Unless otherwise specified at BEDD (Basic Engineering Design Data), TR Unit shall withstand the
following environmental conditions without damage or degradation of operating characteristics.
6.1 Outdoor
6.2 Indoor
Non-Hazardous or Hazardous areas as per „Area classification Layout‟.
Temperature: Ambient temperature 0°C to 55°C (with metallic surface temperature
reaching to 90°C due to solar radiation)
Relative Humidity: 0-100%
Atmosphere: Coastal
Indoor Condition: Temperature range 0°C to 40°C,
Relative Humidity: 50%
7. Transformer Rectifier (TR)
7.1 General
7.1.1 The TRs shall be oil cooled if to be installed in outdoor environment. Air cooled units shall
only be used when they are to be installed inside an air conditioned room.
7.1.2 The TR units shall have switchable constant current, constant voltage mode.
7.1.3 All outdoor TR units shall be provided with an integral shield to protect the unit and control
cabinet from direct sunlight impingement.
7.1.4 All TR units shall be supplied with a synchroniseablebuilt-in currentinterrupter.
7.1.5 TR shall be selected with 50% excess capacity to allow for adjustments during the life of the
cathodic protection system and to prevent damage due to voltage overload.
7.1.6 A Silica gel breather shall be installed for each oil cooled TR to absorb moisture for
transformer having conservator type oil preservation system.
7.2 Design Life
The TR shall be designed to provide service for a minimum of 30 years of continuous operation
with minimum level of maintenance.
7.3 Design and Construction – Mechanical
7.3.1 All external and internal oil chamber seams shall be seal welded. Welding shall comply with
AWS D1-1.
7.3.2 Monitoring, control and protection components shall be installed in such a manner as to
permit rapid and convenient changeover in the event of failure of a component or component
group.
7.3.3 Enclosures:
a. The electrical components comprising the transformer, rectifier, instruments, monitoring
and control equipment shall be installed and/or housed within a weatherproof, impact
resistant and corrosion protected enclosure. The enclosure shall be provided in
accordance with SES E02-E02 for protection against the worst case environment as
follows:
i. Outdoor enclosure shall be minimum NEMA 4X and fabricated thick mild steel
sheet. All external surfaces shall be protected against corrosion using zinc flame
spray and 2 part Epoxy/Polyurethane coating system.
ii. Indoor enclosure shall be fabricated of mild steel with epoxy powder coating. The
enclosure shall be in accordance with NEMA 4.
iii. Hazardous area enclosure shall be explosion proof and type NEMA 7 for indoor
enclosure and NEMA 8 for outdoor enclosure, and shall be classified for the area
and the appropriate gas group as per NEMA 250.
iv. For TR units located in hazardous areas, the instrument control cabinet and circuit
breaker housing shall be made of corrosion resistant and suitable for the
Hazardous area of location in accordance with SABIC standard E02-E02. The
equipment shall be certified by an approved internationally recognized American
or Eurpean standards authority for use in hazardous area with clear legible name
plate at the enclosure.
b. Enclosure construction and sealing shall comply with NEMA ICS 6 unless stated
otherwise. Quick release (no tools needed) with minimum two latches shall be provided
to secure all enclosures. Nitrile rubber or equivalent material shall be used for gasket and
shall be fastened to the TR with epoxy adhesive. Insetting the gasket within a continuous
three sided frame. Gaskets shall be one-piece construction, fully framed and secured to
the tank lid.
c. The control enclosure shall be attached to the end of the oil tank and readily accessible
to conduits. Sizing shall be ample and fully compatible with the control panel and all
electrical terminals to allow easy access and removal of each.
d. The oil cooled TR shall be supplied with temperature/oil level gauge meter to indicate the
actual oil tank temperature and oil level. The temperature and oil level gauge shall be
visible and mounted outside the oil tank.
e. The oil tank shall be welded both from inside and outside. Tanks shall be suitably
stiffened to prevent warp age during transportation when filled with oil.
f. Base mounted units shall use 100 mm or 4 inch structural channels minimum for
underside clearance. The tank lid shall be hinged with a stop to limit swing to between
100 and 110 degrees from the closed position. Top lip of the tank shall not exceed 132
cm (52 in) above the mounting base. A lockable lid and industrial grade support
permanently attached at both ends of the lid shall be provided to hold the tank lid in the
open position even during strong winds.
g. Control enclosures for oil filled rectifier enclosures shall include a pocket to keep the
“Installation, Operating and Maintenance Instructions”. The pocket shall be accessible
and shall not inhibit cooling or monitoring/maintenance of the rectifier. The pocket shall
secure the instructions documents during shipment and in high wind conditions with the
enclosure door open.
h. TR Chassis:
i. Air Cooled TR Chassis:
The TR components shall be mounted on a slide out, or tilt out removable chassis.
ii. Oil Cooled TR Chassis:
TR units shall be constructed so that the internal components are mounted on two
removable chassis; one for the transformers and chokes and one for the lighter
components (e.g. diode stacks, lightning arrestors etc.). Each of the two chassis
shall be independently removable, using two lift points, and able to be unbolted from
the tank above the oil level. All interconnecting wiring between these two chassis or
between both chassis and the tank or control enclosure shall be easily accessible
from the top of the tank.
i. Conduit entries shall be provided for AC and DC conductors. The conduit size shall be
1.5 inch, unless otherwise specified. Conduit entries shall be located directly in line with
the conductor termination to avoid cable bending inside the enclosure.
j. Threaded watertight hubs shall be provided from the manufacturer for all conduit entries.
Threaded, compression type hubs are acceptable for non-classified area units. Classified
area units shall have continuously welded hubs and sealing fittings installed on each
conduit entry conforming to NEC requirements.
k. All rectifiers shall be provided with lifting lugs. Four (4) lugs for oil cooled units shall be
provided to support the TR when filled with oil.
l. All oil cooled TR‟s shall be provided with a side or end exposed drain valve at the lowest
area of the tank bottom to remove oil and drain moisture. The drain valve shall be
threaded one inch per ANSI B2.1. The valve shall be shielded by a kick plate extended to
the end of the valve.
m. Liquid fill shall be through a filler pipe with threaded cap. Cold and hot oil levels shall be
permanently indicated inside each oil tank and be visible via an external sight gauge.
n. All wiring shall be identified by the color of the insulation and permanent wire markers.
Each conductor shall have a number or letter and color identifying it, which corresponds
to the operating manual schematic diagram. Adhesive type wire markers are not
acceptable. Markers shall be suitable for oil immersion.
o. All fuses and/or miniature circuit breakers shall be labeled with circuit designation and
fuse characteristics.
p. All major components and fittings within each unit shall be marked and labeled to
indicate technical data relevant to the components using permanent, mechanically
secured, engraved labels. Markings shall include but not be limited to:
Output Circuit Rating
System Positive Terminals
System Negative Terminals
AC Input Terminals
Circuit Control Identification
Max. Operating Voltage
Max. Operating Current
Fuse Ratings
Meter Selector Switch
Meter Circuit Identification
All monitoring socket Terminals
q. Each rectifier shall be provided with a bolted or riveted stainless steel 304, engraved or
stamped nameplate. This nameplate shall be located for easy visibility on the outside of
the enclosure door on all units. For hazardous area TRs, the nameplate shall be located
on the oil enclosure or associated fixtures. Each nameplate shall indicate the following as
a minimum:
Manufacturer and Address
Descriptive Name
Manufacturer’s Serial Number:
Input Rating:
kVA
Nominal Voltage
Current
Single or three phase
Frequency (Hz) – 60
Minimum Power Factor
Output Rating:
kW
Voltage
Current
Oil Capacity: Liters
Maximum Operating Temperature
Date of Manufacture:
7.4 Design and Construction – Electrical:
7.4.1 General
a. Relevant requirements of SES Electrical Design Criteria E02-G01 shall be adhered to.
b. Electrical design and construction shall be rated for the environmental conditions and
comply with international standards such as NFPA 70, National Electrical Code (NEC) or
IEC
c. A continuous input voltage variation of ±10% of the nominal value shall not damage the
transformer or the rectifying element.
d. The TR rated operation frequency shall be 60 Hz, and output waveforms shall be full
wave rectified.
e. Reversal of the input phase sequence on three phase units shall not affect the unit‟s
performance or damage any component.
f. Miniature circuit breakers and/or fuses shall be installed to achieve input overload and
short circuit protection (refer to clause 7.3.3 o).
g. All TRs shall be supplied with approperate size of shunt to measure the applied current.
7.4.2 Each rectifier shall be provided with an external corrosion resistant ground terminal for
connection of up to a 25 mm2
(#4 AWG) size copper ground conductor. Internal equipment
grounding terminal shall be provided.
7.4.3 Cabling and Wiring:
a. Cables and wires shall be stranded copper conductors with PVC or XLPE as per ICEA &
UL requirements..
b. Sufficient space shall be made available within the cabinet to allow the cables to be set to
one side so as not to impede removal or replacement of any component.
c. Wires shall not be taped or spliced between termination points. Wiring shall be bundled
and secured with plastic ties.
d. Conductors penetrating the tank wall shall be suitably sealed to prevent leakage or
wicking of the oil and located at least 75 mm (3 in) above the hot oil level.
e. Only one conductor per terminal shall be permitted. Circuit expansion shall be achieved
by standard bridging strips, barrels and screws.
f. All cables and wiring shall be appropriatley identified at each end using labels intended
for this purpose.
7.4.4 Terminals:
a. All internal wire terminations shall be made with pre-insulated solderless full ring crimped
lug connectors properly sized for conductors and terminals. Soldered connections are not
acceptable.
b. The positive and negative terminal posts shall be screw terminal type machined from
brass and shall be positioned to permit ready and easy connection of the DC cables.
c. AC input connection shall be made at a terminal block which shall provide clearly
identified connections. The incoming lugs shall be covered with removable clear
polycarbonate shield to allow visual inspection and IR scan of the terminal with the unit
energized.
d. There shall be DC positive and negative terminals for each output having a nominal size
of 25mm
2
diameter. The corresponding negative screw terminal shall also be of 25mm2
diameter. These terminals shall be clearly marked by “Positive” and “+” and “Negative”
and “-“to indicate their polarity.
e. Terminal blocks shall have tin or silver plated screw type terminals with full insulating
barriers.
7.4.5 AC Input:
a. The TR unit input voltage, phase, and grounding system shall be designed as specified.
Refer SES E02-G01, Section 4.0 for utilization voltages.The incoming A.C. supply shall
be terminated via an appropriately rated, Switch fuse or Circuit breakers and residual
current device in accordance with SES E02-G01.
b. The input voltage of the supply system may be subject to transient, comprising of voltage
depressions of up to 10% of the nominal voltage. The frequency may occasionally dip to
95% of the rate frequency. In addition the AC supply could on occasions be interrupted,
by power cuts and the TR shall be capable of resisting damage resulting from peak
surges as the AC power supply is instantaneously returned.
c. Design shall allow for AC input wiring to connect to shielded terminal board located near
the top and rear of the control enclosure. Exposed AC input terminals on the front of the
panel board shall not be acceptable. AC terminals shall be accessable to standard
voltmeter test probes.
d. When the TR unit need to be located in hazardous areas, then the AC input and all other
components which are potential spark producing, shall be enclosed in a suitable
enclosure as per NEMA 250 (refer to clause 7.3.3 iii).
7.4.6 DC Output:
a. The current and voltage outputs shall be rated as required by the design, including
sufficient allowance for anticipated changes in current and particularly voltage with time.
b. The current output rating of each independent zone shall not be less than the maximum
allowable anode current capacity of that zone.
c. Full rated DC output Voltage shall be adjustable by not less than 20 equal steps from
approximately 5 % of rated voltage to full rated voltage to full rated output.
d. Maximum allowable operating voltage of different anode systems shall also be considered
in designing the voltage output rating of the units.
e. Output ripple voltage shall not exceed 5% at maximum rated output voltage and current.
f. DC output terminal posts shall have a minimum 76 mm (3 in) clearance from each other
and from all other metal parts and be located at least 200 mm (8 in) above their conduit
entries. Each DC terminals shall be double post type shall be supply with two nuts, two
flat washers, one lock washer and compression lugs. The compression lugs and the post
shall be made of a copper alloy, plated with tin, silver or electro less nickel.
7.4.7 DC Output Control:
a. DC voltage or current output control shall be step less phase control by potentiometer
adjustment within ±1% accuracy from zero to rated output. Link bars, tap switches,
autotransformers or motor driven apparatus for DC output control shall not be acceptable.
b. The transformer rectifier shall be designed so that on load adjustment of the output may be
carried out safely. Rectifiers shall be capable of operating continuously at rated output
current at any output voltage from 0 to 100%, without damaging any rectifier components.
c. The output mode shall be switchable as follows:
i. Constant Current Mode.
ii. Constant Voltage Mode.
iii. Automatic Potential Control Mode (shall be provided only as option if so specified).
7.4.8 DC Output Monitoring Facility:
a. Each individual TR unit (i.e. each DC output) shall include two pairs of socket terminals to
facilitate the following independent measurements using a hand held digital multi-meter:
i. Output Voltages
ii. Output currents (by voltage drop across a shunt resistor with an accuracy of ±
0.5%).
iii. Structure potentials with respect to the reference electrodes.
b. For DC outputs, the socket terminals shall be red for the DC positive terminal connections
and black for the DC negative terminal connections. For monitoring unit, the socket
terminals shall be red for the embedded reference electrode terminal connections and black
for the associated steel signal terminal connection.
c. The function and rating of all sockets and the multiplying factor of all shunts shall be clearly
marked.
d. Meters (voltmeter and ammeter) shall be either analog or digital. Combination volt/amp
meters are unacceptable.
e. Analog voltmeter and ammeters for each DC output shall be installed and shall be clearly
visible through a window in the housing. They shall be of the continuous reading meter
type. Meter accuracy shall be a minimum of 1% of full scale at 30C, and shall be
temperature compensated to vary no more than 1% per 10C temperature variation. Scale
faces shall be metal.
f. Analog instrument scales shall be 100 mm (4 in) minimum length and redline or shaded
beyond the maximum rectifier rating. The minimum full scale deflection for analog meter
shall be 130% and maximum 150% of the rate output of the TR. Scale values shall be
marked and labeled in even instruments of volts and Amps. Each scale shall be clearly
labeled in contrasting letters minimum 6mm (1/4 in) as “DC VOLTS” or “DC AMPS”. The
scale face material shall be aluminum. Paper or cardboard scale faces are not acceptable.
g. The TR unit shall have LEDs (light emitting diodes) or other means of indicating A.C power
supply “on” and D.C. output “operational”.
h. DC output current shall be measured with a 50 mV precision block shunt. Shunt size for the
current measurement shall be 25, 50, 75, 100, etc. ampere ratings, to provide a whole
number ratio of current to mV. The shunt shall be accessible without removing the
instrument panel. The shunt rate shall be stamped on the shunt and be visible in the
installed positioned or labeled.
7.4.9 Instrument Panel:
a. Instrument Panel for Non-Hazardous area TR:
All instruments such as ammeters, voltmeters, control switches etc., shall be mounted on a
hinged panel with a minimum of 90
o
C swing capability. The panel shall be held in the
closed position by two (2) wing or knurled captive fasteners. Wiring from the back of the
panel shall be bundled and secured with plastic ties. No field wiring shall terminate on the
swing out instrument panel. The instrument panel should easily swing open to provide
access to back of instruments. Panel material shall be one piece 6 mm (0.25 in) minimum
thickness laminated phenol or UTR fiberglass reinforced laminate with minimum
temperature 155 °C. All connections of load current capacity shall be offset from the
instrument panel by a nut and lock washer.
b. Instrument Panel for Hazardous Area TR:
Each DC meter shall be mounted in a separate, standard glass face explosion proof meter.
7.4.10 A variable timer controlled D.C. relay system interrupting the output to facilitate
“instantaneous off” structure potential measurement shall be provided. The current circuit
breaker on the output shall be capable of interrupting the DC output in a period of less than
0.1 seconds at any load. The interrupter shall be capable of switching the full load current at
maximum output on a variable time cycle of up to 10 seconds “on” and 10 seconds “off”. The
operation of the interrupter shall not affect the electrical supply to, or accurate operation of,
any of the other circuits during its operation.
7.4.11 TR Protection:
a. AC overload and fault current protection shall be provided by a molded case circuit
breaker with a 120% trip rating to provide a disconnect means, short circuit protection and
thermal time delay overload protection. Circuit breaker input and output terminals shall be
made easily accessible for testing through non-metallic guard.
b. Circuit breaker shall contain one pole per input line of AC.
c. A valve type surge arrestor incorporating a silicon material to provide a low resistance
circuit to ground for switching surges shall be mounted across each pole of the AC input
and rated for the proper circuit voltage. The arrestor devices shall be located for easy
replacement. Arrestors and surge protection on units designated for all oil cooled TR shall
be located below the cold oil level.
d. AC input and AC terminals shall be shrouded to prevent accidental contact.
e. A separate isolating unit shall be connected between the AC power input cable and the
TR to allow the safe removal of the TR if necessary.
f. Appropriately rated surge protection shall be provided in the DC output and AC input
circuits.
g. DC fuses shall be rated at not more than 120% of rate current output, 250 volts, and shall
be installed in each positive phase leg.
h. A single fuse on the positive DC output circuit shall provide over current and short circuit
protection to the rectifiying elements.
i. Fuses for hazardous area TR shall be placed inside the oil tank.
7.4.12 Transformers and Chokes:
7.4.13 All TRs, auto and auxiliary power transformers and chokes shall comply with the applicable
portions of IEEE C57.18.10. The minimum winding insulation shall be Class 180. Control
transformers may be Class 150 insulation. The primary and secondary windings shall be
isolated with an electrostatic shield. Chokes and transformers shall be varnish dipped and
baked on all Class AA units and where exposed to air. Limits of transformer winding
temperature for defined load cycles shall be as per Table 10 of IEEE C57.18.10.
7.4.14 Power rectifying diodes and Silicon Control Rectifiers (SCRs) shall be mounted on aluminum
heat sink size to limit device case temperature to 90°C at 50°C ambient conditions and rate
load. Heat sink for air cooled shall be anodized.
7.4.15 The peak inverse voltage rating of diode and SCR shall be 1200 volt (RMS) minimum. The
diode forward current rating shall be a minimum of 50% greater than the full load conducted
current.
7.4.16 Oil cooled TR units shall have a hand removable rectifier element assembly including SCR,
diode and Metal Oxide Varistor (MOV) mounted. All cable/wire disconnected terminals to
remove the rectifier assembly shall be above the hot oil level.
7.4.17 Surge and transient suppression protection for the diode and SCR shall consist of MOV
across each AC input terminal to rectifying element and electronics board to protect the
semiconductors and across the DC output terminals. The MOV shall be voltage coordinated
for the circuit and component to be protected. Each MOV shall be rated of 15% minimum
above nominal line voltage.
8. Remote Monitoring System (RMS)
8.1 General
8.1.1 The TR units supplied with remote monitoring system (RMS) shall be delivered as a
complete system comprising hardware and software required to: energize, monitor and
control (including current & voltage adjustment) the cathodic protection system from a remote
controller. Operation of this system shall be in accordance to L02-M01.
8.1.2 Prior to procurement of TR units and the remote monitoring system, the contractor shall
submit details of the proposed system including features and specifications of both hardware
and software for SABIC review and approval.
8.1.3 Cathodic Protection system shall be installed with remote monitoring system (RMS) for all
structures specified in SES L02-E01 & L02-E02.
8.1.4 Each TR unit shall be able to operate and control through a remote computer and also be
operational as a standalone system which can perform current & voltage adjustments,
current-on, instant-off and depolarized potential measurements, and data storage for a
defined period of time for all these measurements.
8.1.5 The Power Supply and Remote Monitoring System (PSRMS) shall enable the operator to
fully monitor and control the CP installation locally (as a standalone system) and/or from a
remote address.
8.1.6 Any failure in the PRMS system shall not affect the TR manual control or TR performance.
8.1.7 The transmission of the data shall be provided via RS-232 or RS-485 connection and operate
through network cable, fiber optic, GPS or GSM. The communication protocol of the RMC
system can be the Industrial ModBus protocol.
8.1.8 The data shall be real time, accurate and without any time delay. The maximum resolution for
the transmitted data shall be 0.01 V, 0.01 A and 1 mV for output voltage, output current and
potential respectively.
8.1.9 Interrupter shall be GPS synchronized to interrupt the selected number of TR units at the
same time.
8.1.10 The PRMS system shall be capable to control and adjust the TR‟s output through a very
stable and reliable control board.
8.1.11 The PRMS System shall be able to monitor and control any selected location in the network
through a separate personal computer.
8.1.12 The PRMS software shall be able to carry out the following functions as minimum but not
limited to:
a. Energize and de-energize each TR unit independently.
b. Read and set the operating parameters for each TR unit independently.
c. Conduct depolarization and instant off measurements using embedded / permanent
reference cells.
d. Retrieve depolarization and instant off test data, and routine monitoring data stored in
the computer unit. Monitor individual units in real time.
e. Print data for reports.
f. Alarms shall be displayed when the alarm view is opened.
g. Alarms shall be for instant off potential, rectifier current and voltage when exceeding
minimum and maximum limits and maximum temperature.
h. Read and store ‘natural potential’ data for reference electrodes before energizing the
system. Read and store ‘current-on potential’ and Instant-off potential’ data for reference
electrodes after energization of the CP system.
i. Control in either constant current or constant voltage.
j. Set minimum and maximum limits for output voltage (with resolution of 0.01 volts).
k. Set minimum and maximum limits for output current (with resolution of 0.01 amps).
l. Automatically switch on power supply outputs after the completion of instant off tests.
Shows current and voltage for each channel on Power Supply Unit.
m. Show ‘Natural potential’ and ‘Instant-of potential’ for each reference electrode.
n. Display data with zoom functions.
o. Print data and graph.
p. Export data to excel sheet
q. Overview screen shall show plants, structures, anodes and monitoring layouts, CP
drawings and details.
r. A shortcut button shall be installed to the system overview screen.
s. On the graphs, the criteria line shall be added.
t. Log in entry shall be for three levels at least based on SABIC requirements.
u. Export and import data files.
v. System overview screen for checking the functionality of all power supplies (TR units).
w. System overview screen for showing the summary of criteria compliance at
embedded/permanent reference electrode of each zone, or independent output or
structure.
x. Auto commissioning or initial energizing of the multiple zones or outputs at 10%, 25%,
50% and 100% of the design current.
9. Quality Control & Tests:
9.1 General
9.1.1 All equipment and devices shall be manufactured, laid out and wired in accordance with well
established practices such as ANSI C34.2 or IEC , and all necessary quality control checks
and test shall be carried out during various stages to ensure good workmanship, appearance
and reliable operation of every component of the TR unit.
9.1.2 TR manufacturer shall conduct tests at his premises to demonstrate full functional conformity
and fitness for purpose under the audit of SABIC. The results shall be fully documented and
shall constitute part of the permanent records for the works.
9.1.3 The TR unit shall be inspected, tested and satisfactorily pass the following tests. Test results
shall be recorded and a copy submitted to the Design Engineer for approval and records:
a. DC output ripple factor test for each transformer rectifier shall be less than 5%.
b. Temperature rise test shall be run for 48 hours (at least) till getting stable readings. The
maximum acceptable rise in that period from ambient temperature shall be less than
25°C. Temperature test points shall be placed top, middle side, middle back and bottom
of the enclosure. Temperature measurement shall be made by thermocouple or
resistance change method.
c. The efficiency of the overall transformer rectifier with the rectifier adjusted to supply rated
output at rated load shall be greater than 80% and shall be determined by measuring
with a wattmeter and comparing the total power at the transformer secondary output, and
total power at the transformer primary input.
d. The power factor of the rectifiers shall be greater than 80%.
e. The insulation characteristics of primary circuit to secondary circuit, primary circuit to
dead metal parts and secondary circuit to dead metal part shall be sufficient to withstand
a 2000 volt, 60 Hz signal applied for 1 minute. Leakage current shall be less than 5 mA,
and no amount of arcing is acceptable (Dielectric Test).
f. Test shall be conducted to verify that the rectifier shall automatically maintain the set
voltage and current within ± 1% under varying load condition, as long as the output
voltage or current does not exceed the value establish by the voltage or current control.
g. Tests shall be conducted to verify that at the automatic potential control mode, the
desired set potential can be maintained from +2 to -2 V between the structure and
reference electrode. The LCD display shall read the potential between +20 to -20 V.
h. Reference electrode input shall be tested from local control unit, master control unit and
digital multi-meter. The readings shall be accurate and the error percentage shall be less
than 0.5%.
i. Calibration check for all meters.
j. Overload testing for all protection devices.
k. Electrical test shall be:
i. AC Volt Input
ii. AC Amperes Input
iii. Apparent Watts Input
iv. True Watts Input
v. Power Factor
vi. DC Volts Input
vii. DC Amperes
viii. DC Watts Output
ix. Conversion Efficiency
x. Dielectric Strength
xi. Transformer Primary to Ground
xii. Transformer Secondary to Ground
xiii. Transformer Primary to Secondary
xiv. Stack AC to Ground
xv. Stack DC to Ground
l. The remote monitoring and control system shall be tested and physically inspected in the
factory. The test results shall be recorded and submitted for SABIC review and approval.
Testing shall include but not limited to the following:
i. The accuracy of TR voltage and current output shall be tested and synchronized
between the software and actual measured at the TR. The test shall be
conducted at 25%, 50%, 75% and 100% of rated output. The difference between
readings shall not be more than ± 1mV and ± 1 mA.
ii. Input signals of embedded/permanent reference electrode (structure potentials)
shall be measured at the TR/JB/test station and compared with those recorded in
the software. The deference shall not be more than ± 1mV.
iii. All TR units with RMS shall be tested. The TR shall give stable current and
voltage output and provide a cross check for any variations caused by RMS.
iv. All RMS features in section 8 and approved manufacturer‟s specifications shall
be checked and verified.
10. Recommended Spare Parts
A complete list of recommended spares for two (2) years shall be provided by the vendor.
11. Operating Instructions & Maintenance Handbook
The unit shall be supplied complete with an operation manual/ maintenance handbook which shall
include operating instructions. The following data shall also be included with the manual:
11.1 General
11.1.1 A copy of the acceptance test data and certificate
11.1.2 Drawings showing:
a. Cabinet manufacturer detail
b. Internal layout with component names, size and supplier
c. Schematic circuit with component name, rating and supplier
d. Panel layout
e. Module detail (other than proprietary information).
12. TR Shipping
The TR unit shall be appropriately packed for loading/unloading and transportation as per SESZ01-G07.
Particular care shall be taken to prevent damage due to mishandling or the ingress of
dust or water whilst in transit. Steel support, conduits, externally mounted devices and other such
items shall be supplied separately and assembled at site before installation