Costan EPTAGLOO, Installation, User And Maintenance Manual

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COSTAN TECHNICAL DOCUMENTATION REVISION STATUS
TRUE COPY PAGE 10 OF 8
PRODUCT: EPTAGLOO ORD DATE CHANGE ORDER OF THE SIGNED DATE OF 1st ISSUE
DOC. no. QSM0000406A CHAP. No.: 050 A 23.Feb.2010 RANGE EXTENSION ORIGINAL 13/June/07
CHAPTER: ELECTRICAL PANEL
TECHNICAL SPECS ISSUED BY MKT
Motor contactors have been designed for a million maneuvers on average (1 maneuver =
1on+1off) with the maximum rated current in category AC3. Considering that the limit of
an average compressor is 10-12 starts per hour, the useful life of a contactor will be
10
years if their starts occur under the severest conditions (continuous breakaway - maximum
compressor load - rated current). Also considering that in systems including several
compressors, these are made turn over by the electronic controller, that under normal
operation conditions electric motors are used by 50-40% of their rated nominal current and
considering also that systems have dead zone periods (in which systems are stable and
compressors are not required to go on or off), contactor life must necessarily be longer than
the length they were designed for.
(Details on contactor life taken from catalogue SIEMENS SIRIUS 3R).
It is worth underlining and bearing in mind that in our case, the life of a contactor is
not
determined by the number of maneuvers it performs (which, considering the amperage
rating in category AC3 may total 250 maneuvers/hour), but by the compressor: for
small/medium compressors max. 10-15 maneuvers/hour; large compressors: max. 6-7
maneuvers/hour. Exceeding the compressor maneuvers/hour physical limit may damage
the equipment itself and even cause short circuit in the electric motor.
Short circuit is prevented by the overcurrent device protecting the compressor.
After a short-circuit has occurred, both the overcurrent cutout and the contactor will
have to be replaced.
(cfr. chapter 23 “important notice”).
8. Condenser fan circuit Diagram UTQ39080/sheet 8.
8.1 Compact system SIEMENS SIRIUS S0.
8.1.1 For electrical panels with overcurrent protection: fan protection by fuse-fitted circuit
breakers 10,3X38 and the relevant aM fuses.
8.1.2 For optional electrical panels with RCBO (residual overcurrent protection):
overcurrent cutout Siemens Sirius series S0 with release coil actuated by residual current device
Merlin Gerin RH99M+tore 30 .
8.1.3 Contactor SIEMENS S00/0.
8.2 The power circuit for the fan must be wired up strictly following the phase sequence L1-L2-
L3.
9. Control circuit to operate the machine-cooling fans and the plant-room air expeller:
Diagram #UTQ39090/sheet 9.
9.1 Fuses for machine-cooling fans (if any)
9.2 Fuses for the power board: plant-room air-expellers.
10.Control electronics diagram #UTQ039E_0/sheet 10/E.
10.1 Controllers
10.1.1 Box under Costan code UQ39E001E wired to DANFOSS EKC331/T
Low-pressure electronic regulation by the dead zone principle. High pressure
regulation by pressure-switches.
10.1.2 box under Costan code UQ39E002E wired to CAREL IR32Z3
Low-pressure regulation by electronic pressure-switch and the stepper principle.
High pressure regulation by pressure-switches.
10.1.3 Box under Costan code UQ39E003E wired to DANFOSS AK-PC530
Low and high pressure electronic regulation by the dead zone principle.