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1 HOW TO USE THIS MANUAL
The following conventions are used in this manual.
Callout column:
Callouts on the topics described are placed to the left of the text to allow the user to find the desired information quickly.
Icons
Some parts of the text are highlighted using icons that have the following meanings:
NOTE: Draws attention to a specific topic that users should take into account.
TIP: Highlights a suggestion that helps users to understand and use the information on the topic described.
WARNING: Highlights information that may damage the system or place persons, equipment, data, etc at risk if not known. These sections must
always be read prior to use.
2 INTRODUCTION
The E71R and E72R EcoCool
™
controllers are microprocessor based electronic temperature and defrost controllers for use in compressor-driven commercial
freezers and refrigerators. The E71R includes one relay for a refrigeration compressor or refrigeration solenoid valve. The E72R includes one relay for a
refrigeration compressor or refrigeration solenoid valve and one relay for a defrost heater and optional fan.
3 E71R AND E72R CONTROLLERS
3.1 Overview
E71R / E72R Controller
WARNING: A separate switch must be installed to disconnect the controller, compressor, and fan from line voltage for service.
Both controllers allow configuration of cut-in and cut-out temperatures and defrost scheduling for precise temperature control. An adjustment knob allows
the user to select a configured cold setpoint, warm setpoint, or any setpoint within this range. Optionally, the adjustment knob also can be configured with
ON/OFF functionality to power off the controller for non-service purposes. To prevent setpoint adjustment with the adjustment knob, a fixed setpoint can be
configured. The E71R and E72R can defrost the evaporator using an off-cycle defrost that powers off the compressor for a specified time period or until a
specified evaporator temperature is reached. Additionally, the E72R includes a second relay that can be used to energize a defrost heater or reverse cycle
solenoid valve to defrost the evaporator coil. Controller configuration is designed on a computer using EcoCool configuration software and is downloaded into
the controller from the computer or a copy card.
Three status LEDs (red, yellow, and green) display the system status. Temperature and fault alarms, defrost status, and compressor operation are indicated
by the LEDs.
An optional remote digital display shows the control temperature and, during adjustment, changes to the setpoint. It can be configured to show for the
duration of the defrost cycle the actual temperature, the temperature that was sensed at the moment the defrost cycle started, or dF. The display also
includes three system status LEDs.
Type E7 EcoCool™ Electronic Temperature and Defrost Controllers
©2008 Invensys Controls All rights reserved.
DRAFT VERSION
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