Section 3 — Operation
ATS “HS” Type Transfer Switch
Conductor sizes must be adequate to handle the maximum current to which they will be subjected to, based on the 75°C column of tables, charts, etc. used to size conductors. The installation must comply fully with all applicable codes, standards and regulations.
Before connecting wiring cables to terminals, remove any surface oxides from the cable ends with a wire brush. All power cables must enter the enclosure through the knockouts. If not using the knockouts, entry must be at or below knockouts. If ALUMINUM conductors are used, apply corrosion inhibitor to conductors. Tighten terminal lugs to the torque values as noted in Section 1.2.2, and on the decal located on the inside of the door. After tightening ter- minal lugs, carefully wipe away any excess corrosion inhibitor.
Use a torque wrench to tighten the conduc- tors, being sure not to overtighten, or damage to the switch base could occur. If not tightened enough, a loose connection would result, caus- ing excess heat which could damage the switch base.
Connect power source load conductors to clearly marked transfer mechanism terminal lugs as fol- lows
1.Connect UTILITY (NORMAL) power source cables to circuit breaker.
2.Connect EMERGENCY (STANDBY) source power cables to transfer switch terminals E1, E2.
3.Connect customer LOAD leads to switch termi- nals T1, T2.
Conductors must be properly supported, of approved insulative qualities, protected by approved conduit, and of the correct wire gauge size in accordance with applicable codes.
Be sure to maintain proper electrical clearance between live metal parts and grounded metal. Allow at least 1/2 inch for
2.5CONNECTING START CIRCUIT
WIRES
Control system interconnections consist of N1 and N2, T1 and T2, and leads 23 and 194. Control system interconnection leads must be run in a conduit that is separate from the AC power lead. Recommended wire gauge sizes for this wiring depends on the length of the wire, as recommended below:
MAXIMUM WIRE LENGTH | RECOMMENDED WIRE |
| SIZE |
460 feet (140m) | No. 18 AWG. |
461 to 730 feet (223m) | No. 16 AWG. |
731 to 1,160 feet (354m) | No. 14 AWG. |
1,160 to 1,850 feet (565m) | No. 12 AWG. |
|
|
NOTE:
When this ATS is used with an
3.1FUNCTIONAL TESTS AND
ADJUSTMENTS
Following transfer switch installation and inter- connection, inspect the entire installation care- fully. A competent, qualified electrician should inspect it. The installation should comply strictly with all applicable codes, standards, and regula- tions. When absolutely certain the installation is proper and correct, complete a functional test of the system.
Perform functional tests in the exact order pre- sented in this manual, or damage could be done to the switch.
IMPORTANT: Before proceeding with functional tests, read and make sure all instructions and information in this section are understood. Also read the infor- mation and instructions of labels and decals affixed to the switch. Note any options or accessories that might be installed and review their operation.
3.2MANUAL OPERATION
DANGER 
Do NOT manually transfer under load. Disconnect transfer switch from all power sourc- es by approved means, such as the main circuit breaker(s).
A manual HANDLE is shipped with the transfer switch. Manual operation must be checked BEFORE the transfer switch is operated electrically. To check manual operation, proceed as follows:
1.Turn the generator’s AUTO/OFF/MANUAL switch to OFF.
2.Turn OFF both UTILITY (service disconnect cir- cuit breaker) and EMERGENCY (generator main line to circuit breaker) power supplies to the transfer switch.
3.Turn the GENERATOR DISCONNECT SWITCH to the OFF position.
4.Note position of transfer mechanism main con- tacts by observing the moveable contact carrier arm. This can be viewed through the long narrow slot in the inside cover of the ATS. The top of the moveable contact carrier arm is yellow to be eas- ily identified.
•Manual operation handle in the UP position - LOAD terminals (T1, T2) are connected to UTIL- ITY terminals (N1, N2).
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