Generac
®
Power Systems, Inc.
17
Section 3 — Operation
Generac Liquid-cooled 20 kW Generator
3.10 MANUAL OPERATION
Do NOT manually transfer under load.
Disconnect transfer switch from all power
sources by approved means, such as a 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 and EMERGENCY
power supplies to the transfer switch, with what-
ever means provided (such as the main line cir-
cuit breakers).
3. Note position of transfer mechanism main con-
tacts by observing display windows in “A” and “B”
in Figures 3.4 and 3.5 (on page 18) as follows:
• Window “A” ON, Window “B” OFF - LOAD termi-
nals (T1, T2) are connected to UTILITY terminals
(N1, N2).
• Window “A” OFF, Window “B” ON - LOAD termi-
nals (T1, T2) are connected to EMERGENCY ter-
minals (E1, E2).
Do not use excessive force when operating
the transfer switch manually or the manual
handle could be damaged.
Figure 3.4 — 200 Amp, 2-pole Transfer
Mechanism
3.10.1 CLOSE TO NORMAL SOURCE SIDE
Before proceeding, verify the position of the switch by
observing window “A” in Figure 3.5 on page 18. If win-
dow “A” reads “ON”, the contacts are closed in the
normal position, no further action is required. If it
reads “OFF”, proceed with Step 1.
Step 1: With the handle attached to the actuating
shaft, move handle in the direction of the
arrow on the switch cover until it stops — DO
NOT FORCE. Release handle slowly to allow
the spring in the switch box to relax. “ON”
now appears in Window “A” and “OFF”
appears in Window “B”.
3.10.2 CLOSE TO EMERGENCY SOURCE SIDE
Before proceeding, verify the position of the switch by
observing window “B” in Figure 3.5 on page 18. If
window “B” reads “ON”, the contacts are closed in the
EMERGENCY (Standby) position. No further action
is required. If it reads “OFF”, proceed with Step 1.
Step 1: With the handle attached to the actuating
shaft, move the handle in the direction of the
arrow on the switch cover until it stops - DO
NOT FORCE. Release handle slowly to allow
the spring in the switch box to relax. “OFF”
now appears in Window “A” and “ON” appears
in Window “B”.
3.10.3 RETURN TO NORMAL SOURCE SIDE
Manually actuate switch to return Window “A” to the
“ON” position.
3.11 VOLTAGE CHECKS
1. Turn ON the UTILITY power supply to the trans-
fer switch with whatever means provided (such as
the UTILITY main line circuit breaker).
PROCEED WITH CAUTION. THE TRANSFER
SWITCH IS NOW ELECTRICALLY HOT. CONTACT
WITH LIVE TERMINALS RESULTS IN EXTREMELY
HAZARDOUS AND POSSIBLY FATAL ELECTRI-
CAL SHOCK.
2. With an accurate AC voltmeter, check for correct
voltage.
Single-phase utility supply:
Measure across ATS terminal lugs N1 and N2; N1
to NEUTRAL and N2 to NEUTRAL.
3. When certain that UTILITY supply voltage is cor-
rect and compatible with transfer switch ratings,
turn OFF the UTILITY supply to the transfer
switch.
DANGER
◆
◆
◆
STANDBY
SUPPLY
CUSTOMER
UTILITY
SUPPLY
/NORMAL
LOAD
E1
N2
N1
T1
T2
E2
TRANSFER SWITCH
RATED VOLTAGE
RATED CURRENT
200 AMP
0C8884
600 VAC CSA
480 VAC UL
XXXXXX
STANDBY
T2
B
OFF
A
UTILITY
ON
B2
A1
T1
CHANGE
OVER
DISPLAY
"B" POWER SOURCE
LOAD SIDE OF SWITCH
"A" POWER SOURCE
AUXILIARY
SWITCH
MANUAL
HANDLE
INLET
OPER. CIR.
TERMINALS
*
*
*
*
!
!
DANGER