STANDARD SPECIFICATION FOR COLD JUNCTION COMPENSATION BOXES (CJCB)

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1 SHEET 1 of 5 STANDARD SPECIFICATION FOR COLD JUNCTION COMPENSATION BOXES (CJCB) SPECIFICATION NO.: PES BHARAT HEAVY ELECTRICALS LIMITED POWER SECTOR PROJECTS ENGINEERING MANAGEMENT NOIDA INDIA

2 SHEET 2 of 5 COLD JUNCTION COMPENSATION BOXES (CJCB) Field mounted cold junction compensation Boxes shall be provided to maintain a constant reference junction temperature of 60 deg.c for T/C signals. Compensation shall be provided for both elements of dual T/C. Remote monitoring of CJCB inside temperature in BHEL supplied DCS will be provided for each CJCB. Cold junction compensation boxes shall be as per following specification Requirements: 1.01 Mounting : Field mounted 1.02 Enclosure : IP-55 as a minimum 1.03 Cable entry : From bottom through cable glands forming part of CJC Box Power supply : 24 V DC ± 10% In-built indication : In built power supply indication lamp Reference junction temp. : 60 deg. C 1.07 Automatic Temp. control : To be provided. control 1.08 Input signals : Type K/R/T 1.09 Terminal Blocks : As per actual requirements (Cage clamp type make phoenix/ wago) 1.10 Reference junction temp. : + 0.5oC max. (for K-type) / 2.0o C max.(for R deviation type) 1.11 Effect of tempeture : + 0.1% per 10o C 1.12 No.of Channels : a) K-type -12 channels (i.e. for 6 nos. of b) K- Type - 24 channels (i.e. 12 nos. of c)r- Type - 12 channels (i.e. 6 nos. of d)t- Type - 12 channels (i.e. 6 nos. of

3 SHEET 3 of CONSTRUCTION The thermostat unit together with metal block and thermocouples shall be mounted on mounting plate. All the connections are to be terminated on cage clamp type 2.5 mm2 terminal blocks. Then whole assembly is mounted in a junction box. JB s shall be made up of 4mm thick reinforced glass fiber polyester painted with 631 of IS5 (semi-glossy). Paint thickness micron THERMOSTAT UNIT 3.01 SCOPE Electronic unit for maintaining temperature of metal block at 60 deg.c Thermocouple elements as per standards with tolerance spot welded of 0.5mm and terminal resistance of 2.52 ohms fixed in a metal block, as per specification Necessary insulation for the metal block and electronic circuit Terminal block cable channels to be mounted on mounting frame with electronic unit and completely wired One number 4 wire RTD for 0 to 100 deg.c to be provided and wired to terminals. Accuracy of regulation : deg. Time for heating up : < 30 minutes. Power consumption : < 12 VA Routine test : a) HV, IR & functional test certificates to be submitted along with supplies. b) Functional check : The functional test shall include. i) Measurement of resistance of RTD at specified cold junction temperature. ii) Measurement of EMF of all thermocouples at specified cold junction temperature. Supplier shall write down a procedure for ensuring other functional requirements as per specification and furnish to BHEL for approval. b) Burn in Test: The assembled and tested modules are subjected to a burn in test as follows, Duration : 96 hours Temperature : 70 deg. C + 2 deg.c Status of EUT : Powered ON

4 SHEET 4 of 5 Sample size : 100% NOTE : All PT 100's used in the circuit will be of class A type and have a tolerance of ohm or deg.c at 0 deg.c. And ohm or deg.c at 100 deg.c DOCUMENTS The bidder shall submit the following documents along with the offer Complete BOM as per enclosed format for CJC Box including all necessary accessories with relevant catalogs Complete technical literature for CJC Boxes Proposal data sheets duly filled Clause-wise compliance/deviation list 5.00 REMARKS etc. Subsequent to order, bidder to furnish filled in BOM / schematics / GA drgs 6.00 INSPECTION/TESTING Shall be as per check list CE-415-GNGR-017, Rev 00

5 SHEET 5 of 5

PURCHASE SPECIFICATIONS 500KVA DRY TYPE TRANSFORMER FOR OIL RIG APPLICATIONS

PURCHASE SPECIFICATIONS 500KVA DRY TYPE TRANSFORMER FOR OIL RIG APPLICATIONS PURCHASE SPECIFICATIONS OF 500KVA DRY TYPE TRANSFORMER FOR OIL RIG APPLICATIONS SPECIFICATION NO. : OR12423 REVISION NO. : Rev 00 DATE : 01.03.2011 DISTRIBUTION : PI - 4 copies O/C - 1 copy PREPARED BY