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IB140036EN
Instruction Booklet
Page
20
Effective: October 2014
O&M Manual for 40-1200A (480/600 Vac) ATC-900 3-Position,
Open/Closed Transition Contactor Based Transfer Switch
Section 5: Operation
5.1 General
An ATS provides a power contactor to connect and disconnect
the load to and from the Source 1 and Source 2 power sources
(Section 3.2.1).
5.2 Manual Operation (Open Transition and Close
Transition Transfer Switch)
WARNING
DO NOT ATTEMPT TO MANUALLY OPERATE THE ATS WITH
SOURCE 1 OR SOURCE 2 AVAILABLE.
WARNING
HIGH VOLTAGES ARE PRESENT IN AND AROUND TRANSFER
SWITCH EQUIPMENT. BEFORE ATTEMPTING TO MANUALLY
TRANSFER, DISCONNECT THE LINE POWER FROM THE EQUIP-
MENT BEING SERVICED BY OPENING AND LOCKING OUT, IF POSSI-
BLE, THE NEXT HIGHEST DISCONNECT DEVICE. FAILURE TO
FOLLOW THIS PROCEDURE COULD CAUSE SEVERE PERSONAL
INJURY AND/OR DEATH.
ALWAYS TURN THE SOURCE 1 POWER OFF AND TURN THE
SOURCE 2 (IF A GENERATOR) CONTROL SELECTOR SWITCH TO
THE “OFF” POSITION BEFORE ATTEMPTING A MANUAL TRANS-
FER.
To manually operate:
1. Disconnect all sources of power.
2. Disconnect the J7 connector from the ATC-900 controller.
3. Depress the “trip” button located on the operating mecha-
nism of the contactor to bring the contactor to neutral (trip)
position.
4. Locate the manual lever on the left side of the contactor.
5. Locate the handle used to manually transfer the switch.
6. Attach the handle to the manual lever (see Figure 19A &
19B).
7. Rotate the lever up to go to Source 1.
8. Depress the “trip” button located on the operating mecha-
nism of the contactor to bring the contactor to neutral (trip)
position.
9. Depress the “select” button located on the operating mecha-
nism of the contactor and rotate the lever up keeping the
“select” button depressed to go to Source 2
MANUAL
SELECT BUTTON
TRIP BUTTON
OPERATING
HANDLE
Figure 15A. ATS Manual Operating Handle in Use (Open
Transition).
MANUAL
SELECT BUTTON
TRIP BUTTON
OPERATING HANDLE
MANUAL
SELECT BUTTON
TRIP BUTTON
OPERATING
HANDLE
Figure 15B. ATS Manual Operating Handle in Use (Close
Transition).