TS 840 TRANSFER SWITCH
PM057 REV 8 10/01/25
16
Thomson Technology
5.3.
TEST MODES
The transfer switch may be tested utilizing the TSC 80 controller push-buttons or optional
four position test switch. A simulated utility power failure condition will be activated when
the test mode is selected. The transfer switch will operate as per a normal utility power fail
condition.
The transfer switch will remain on generator supply until the test mode is terminated. It will
then immediately transfer back to the utility supply and then continue to operate the
generator set for its cooldown period then stop.
Note:
The transfer switch will automatically
return to the utility supply (if within nominal limits) if the generator set fails while in the test
mode.
6.
OVER CURRENT PROTECTION
Thomson Technology
TS 840
series of Automatic Transfer Switches may be supplied with or
without integral over current protection as described below:
6.1.
STANDARD TS 840 AUTOMATIC TRANSFER SWITCH
The standard TS 840 Automatic Transfer Switch does not contain any integral over current
protection and requires upstream over current protection devices for both Utility and
Generator sources. The Standard TS 840 is rated for 100% continuous loading and can
withstand a maximum short circuit fault current as noted in
Section 15
of this manual. The
standard TS 840 transfer switch model without integral over current protection is identified
in the product model code. Refer to
Section 4.1
of this manual for further details on model
coding
.
6.2.
OPTIONAL TS 840 AUTOMATIC TRANSFER SWITCH WITH INTEGRAL
OVER CURRENT PROTECTION
TS 840 transfer switches will have integral over current protection supplied on the Utility
source as standard. The type of over current protection utilized is dependent upon ATS
amperage size and optional features specified. For transfer switches rated 100A through
200A, over current protection is non-adjustable thermal-magnetic type trip units. For
transfer switches rated 400A through 800A over current protection is adjustable electronic
type with long time & instantaneous trip unit elements with optional ground fault protection
elements.
