Operating Guide
Operation
12 Automatic Transfer Switch Owner’s Manual
Close to Generator Source Side
Before proceeding, verify position of transfer switch by
observing the position of the manual operation handle in
Figure 3-1. If manual operation handle is DOWN, con-
tacts are closed in generator (standby) position. No fur-
ther action is required. If manual operation handle is UP,
pr
oceed with Step 1.
1. With
manual operation handle inserted into mov-
able contact carrier arm, move manual operation
h
andle DOWN. Hold on to manual operation han-
dle as it will move quickly after the center of travel.
2. Rem
ove manual operating handle from movable
contact carrier arm. Return manual operation han-
dle to storage bracket.
Return to Utility Source Side
Proceed as follows to return to utility source side:
1. Ma
nually actuate transfer switch to return manual
operating handle to the UP position.
2. Rem
ove manual operating handle from movable
contact carrier arm. Return manual operation han-
dle to storage bracket.
Voltage Checks
NOTE: Use the Digital Multimeter (DMM) LowZ low input
impedance setting to collect accurate voltage measure-
ments. LowZ eliminates the possibility of inaccurate
ghost voltage readings, also known as phantom voltage
or stray voltage readings. See DMM manufacturer’s liter-
ature for additional information.
Utility Voltage Checks
Proceed as follows to check utility voltage:
1. T
urn on utility power supply to transfer switch using
utility service disconnect circuit breaker.
2. With
an accurate AC voltmeter, check for correct
voltage. Measure across ATS terminal lugs N1 and
N2; N1 to NEUTRAL and N2 to NEUTRAL.
Generator Voltage Checks
Proceed as follows to check generator voltage:
1. Se
lect MANUAL mode on generator panel. Gener-
ator will crank and start.
2. Allow
generator to stabilize and warm up at no-load
for at least five minutes.
3. Set
generator's main circuit breaker (CB1) to ON
(CLOSED).
4. V
erify no-load, voltage, and frequency with an
accurate AC voltmeter and frequency meter. Mea-
sure across ATS terminal lugs E1 to E2; E1 to
N
EUTRAL and E2 to NEUTRAL.
Frequency 60–62 Hz
Terminals E1 to E2 240–246 VAC
Terminals E1 to NEUTRAL 120–123 VAC
Terminals E2 to NEUTRAL 120–123 VAC
5. Turn off generator supply to transfer switch when
generator supply voltage is correct and compatible
with transfer switch ratings.
6. Set
generator main circuit breaker (CB1) to OFF
(OPEN).
7. Pre
ss OFF on generator panel to shut down gener-
ator.
IMPORTANT NOTE: DO NOT proceed until generator
AC
output voltage and frequency are correct and
within stated limits. If no-load voltage is correct but
no-load frequency is incorrect, engine governed
speed may require adjustment. If no-load frequency
is correct but voltage is not, voltage regulator may
require adjustment.
Generator Tests Under Load
Proceed as follows to perform generator tests under
load:
1. Set
generator main line circuit breaker (MLCB) to
OFF (OPEN).
2. Set
utility service disconnect circuit breaker of the
transfer switch to OFF (OPEN), and turn OFF
(OPEN) all load circuit breakers.
3. Ma
nually actuate transfer switch main contacts to
emergency (STANDBY) position. See Manual
Operation.
4. Sele
ct MANUAL mode to start the generator. Allow
engine to stabilize for a few minutes, and close lid.
(000129)
DANGER
Electrocution. High voltage is present at
transfer switch and terminals. Contact with
live terminals will result in death or serious
injury.
(000123)
DANGER
Electrocution. Turn utility supply OFF before
working on utility connections of the transfer
switch. Failure to do so will result in death or
serious injury.
(000129)
DANGER
Electrocution. High voltage is present at
transfer switch and terminals. Contact with
live terminals will result in death or serious
injury.










