CONTROLLERSeries 185
2
381333–319 E
The Group 4 digital Controller is used in ASCO Series
185 automatic transfer switches. It provides the sensing,
timing, and control functions for the ATS. This micro–
processor–based controller includes built–in control
buttons and status lights for control of the ATS and
generator.
Utility
Acceptable
light
Generator
Acceptable
light
Load on
Utility light
Load on
Generator
light
Set Engine
Exerciser
button
Automatic
Generator
Exerciser
light
Bypass
Time Delay
button
Transfer
Test
button
clock
battery
cover
seepage3
Figure 3. Front view of controller.
1 --- P u s h B u t t o n s
On the front control display are three push buttons that
control the operati on of the generato r a nd the ATS.
Before using the transfer test button, be sure that
conditions are safe for running the generator and
for load transfer.
Transfer Test
Use this button to test the system. This operation starts
the generator and transfers the load. Be sure that
conditio ns are safe to do this operation.
Bypass Time Delay
Use this button to cancel the active time delay or exercise
period (stops the generator after cooldown).
Set Engine Exerciser
Use this button to set the automatic generator exerciser
(page 3).
2 --- I n d i c a t o r L i g h t s
On the front control display are five lights that indicate
the status of the sources and the ATS.
Utility Acceptable
This light indicates that the utility voltage is acceptable
for connection to the load.
Generator Acceptable
This light i ndicates that the generator voltage i s
acceptable for connection to the load.
Load on Utility
This light i ndicates that the load is connected to the
utility.
Load on Generator
This light i ndicates that the load is connected to the
generator.
Automatic Generator Exerciser
This light indicates the status of the generator exerciser:
--- blinks during the exercise period (including cooldown).
--- stays on when the exerciser has been set.
--- is off when the exerciser has not been set.
