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Defrost Duration
Specifies the maximum duration of a defrost cycle (also called failsafe). When the Defrost Duration time expires the defrost cycle ends and, if Drip Time is
configured, the Drip Time starts. If Drip Time is not configured, the controller immediately powers on the compressor and resumes refrigeration.
Drip Time
Specifies how long the controller waits to resume refrigeration after defrost. During drip time, the compressor and defrost relay (E72R only) are de-energized
to allow water to drip off of the coil.
NOTE: If the evaporator fan is wired to the NC contact on the defrost relay (E72R only), the fan will power on at the end of defrost. To delay the fan action
until drip time is expired use an external fan delay thermostat.
Temperature Initiated Defrost Function
Select Enable to allow defrost based on a comparison of the air space temperature and the evaporator temperature. Specify the difference in sensed
temperature (control sensor minus evaporator sensor) that initiates defrosting. Enter the Temperature Initiated Defrost Time Delay to specify how long the
measured temperature difference must exist before defrost starts. Enter the Temperature Initiated Defrost Time delay after Defrost to specify how long
the controller waits after the termination of a defrost cycle or drip time (depending on configuration) before it allows a temperature initiated defrost. This
delay allows the sensed temperatures to return to normal before a temperature initiated defrost cycle can occur.
NOTE: Evaporator Temperature Sensor on the Configuration tab must be enabled to configure and use the Temperature Initiated Defrost Function.
6.2.5.4 Alarm
Use the Alarm tab to specify temperature conditions that illuminate the alarm LED on the controller and on the display.
Temperature Alarm Enable
Select Enable to enable temperature alarms or select Disable to disable the setting and display of temperature alarms.
NOTE: Temperature Alarm Enable does not affect alarms due to a control or evaporator sensor short or open circuit, or a firmware (check sum) error.
High Temperature Alarm – Warm Position
Specifies the sensed high temperature setpoint that causes an alarm when the adjustment knob is in the warm position. Control sensor temperatures equal
to or greater than this threshold cause an alarm when the adjustment knob is in the warm position.
Type E7 EcoCool™ Electronic Temperature and Defrost Controllers
©2008 Invensys Controls All rights reserved.
DRAFT VERSION
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