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IB140015EN
Instructional Booklet
Page
20
Effective: August 2014
ATC-900 Magnum Tranfer Switch O & M Manual
4.7 Control Wiring to Magnum Power Case Switch/
Breaker
Control connections to the magnum power case switch can be
made to the terminal blocks mounted above each device. The
dead front needs to be removed first to gain access to the terminal
locations. Typically the Source 1 (Normal) is the upper power
device and Source 2 (Emergency) is the lower power device. The
terminals are numbered the same for each one and also the same
for fixed mounted or drawout designs. An example of the auxil-
iary contacts is shown in typical drawing below.
4.8 Wiring
Power sources, load conductors, and control wiring should be
connected to locations as indicated in the
Customer Wiring Dia-
grams
supplied with the transfer switch equipment.
4.8.1 Engine Start Connection
The engine control contact connections are located on the bottom
area of the switch at a terminal block and are Red. All customer
connections are located there. The S2 generator start's terminal
blocks are red in color
Note:
Prior to making the engine start connection to the switch on bypass
isolation units, set the engine generator controls selector switch in the OFF
position to prevent an unwanted engine start. A contact closes between
these terminal blocks when an engine start signal is provided by the ATS
logic.
4.8.2 ALARM CONTACTS (CLOSED TRANSITION ONLY)
Closed transition only
ATSs are provided with an extra shunt trip
on the Source 1 device. This shunt trip is energized when the
Time Delay Utility Parallel (TDUP) times out (preset by user), thus
opening the source device. The TDUP timer starts timing when
both sources are paralleled. Refer to the IQ Transfer instruction
book for additional alarms.
S1A29
S1A30
S1B25
S1B18
S1B19
S1B20
S1B21
S1B24
S1B25
S1B23
S1B26
S1B27
S2A29
S2A30
S2B25
S2B18
S2B19
S2B20
S2B21
S2B24
S2B25
S2B23
S2B26
S2B27
POSITION INDICATION CONTACTS SOURCE 1/SOURCE 2 ATS
CAUTION
POWER CONDUCTORS AND CONTROL WIRING MAY HAVE VOLT-
AGE PRESENT THAT CAN CAUSE SEVERE PERSONAL INJURY OR
DEATH. DE-ENERGIZE ALL POWER OR CONTROL CIRCUIT CONDUC-
TORS BEFORE BEGINNING TO PERFORM ANY WIRING ACTIVITY TO
OR WITHIN THE TRANSFER SWITCH EQUIPMENT.