Bard W3RV2-R Literature Assembly page 99

Brownout Protection with Adjustment
Brownout protection may be necessary if the utility
power or generator power has inadequate power to
prevent the voltage from dropping when the compressor
starts. This is rare but can happen if the generator
is undersized at the site or if the site is in a remote
location far from the main power grid. Under normal
circumstances, allowing the brownout to be ignored for
a time period should not be needed. The 8201-169 is
shipped in "0" do not ignore position.
If ignoring the brownout is needed because of the
above conditions, three preset timers can be set by DIP
switches in order to delay signaling a power brownout
for a specific length of time after compressor contactor
is energized. This allows the compressor a time period
to start even if the voltage has dropped and allows
the voltage to recover. This delay only happens when
the CC terminal energizes. The delay can be set to
1, 5 or 10 seconds; time is not cumulative—only
the longest setting will apply. If the voltage recovers
during the brownout delay period, the compressor will
High Pressure Switch
18-30 VAC Input
Y Input from Thermostat
and High Pressure Switch
Troubleshooting Light
Low Pressure Switch
Manual 7960-805A
Page 2 of 2
start. If the voltage doesn't recover during the time
period, a brownout condition will be detected and the
blue LED will flash. A flashing blue LED indicates
that a brownout condition was sensed; the control will
continue to flash the blue LED until the Y call has been
satisfied. The compressor will try to start again after the
delay-on-break timer expires.
If user chooses the "0" do not ignore position when
the site has inadequate utility or generator power, this
could lead to the compressor never starting. The control
will see the brownout immediately and not start.
A common scenario and one that has been seen in the
field is when a unit or units switches from utility power
to generator power. With slower transfer switches, the
time delay between the utility power and generator
power didn't cause a problem. The units lost power,
shut off and came back on line normally. With the
introduction of almost instantaneous transfer switches,
the millisecond long power glitch can be enough that
the compressor will start to run backwards. In this
scenario, the CCM will catch this and restart the units
normally.
FIGURE 1
S8201-169 Compressor Control Module
Brownout Ignore Time DIP Switches*
* Turn on only one switch for that specific ignore time setting
Compressor Contactor Output
Alarm Output
Common
Delay-on-Break Time
Adjustment Potentiometer