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Stand-alone and Master-Slave Control Option
The Wizard WEC-1ZN (WDC), WEC-2ZN, WEC-3ZN, and WEC-4ZN Multi-Zone Evaporator Control Systems with defrost of up to 4 rooms with the following stand-alone and Master-Slave control option:
| Wizard Multi-Zone Evap Ctrl Config Option |
| Model Descrition |
Stand-alone Control |
Master Control |
Slave Control |
Total Zone Controls |
| WEC-4ZN |
4 |
--- |
--- |
4 |
| 2 |
1 |
1 |
4 |
| 1 |
1 |
2 |
4 |
| --- |
2 |
2 |
4 |
| --- |
1 |
3 |
4 |
| WEC-3ZN |
3 |
--- |
--- |
3 |
| 1 |
1 |
1 |
3 |
| --- |
1 |
2 |
3 |
| WEC-2ZN |
2 |
--- |
--- |
2 |
| --- |
1 |
1 |
2 |
| WEC-1ZN |
--- |
1 |
--- |
1 |
Features
Each control can defrost either together or separately, depending upon time or using a separate temperature termination sensor input for each system:
Evaporator Valve Group Status Monitor
Multi-Function Defrost Clock
Temperature Control
Temperature Monitoring and Alarming
Load Shedding Control
System Shutdown
Temperature Recorder
Alarm System
Evaporator Valve Group Status Monitor
The WEC Multi-Zone Control has a series of status LEDs on the front panel that allows the user to easily determine the status of the Evaporator Valves and contactors.
Defrost Control
The WEC Multi-Zone Control is an electronic control and time clock. The time clock can operate up to 8 defrost cycles per day with three separate defrost schedules as well as a manual defrost. The defrost can be either gas, electric, water or off-time defrost. The WEC Multi-Zone Control will cycle all valves necessary to perform a defrost of some of the more complex refrigeration systems.
During a defrost cycle the control will sequence through the following cycles as required:
| Hot Gas Defrost |
Electric Defrost |
Water Defrost |
Off-time Defrost |
- Pump Down Cycle
- Soft Gas Cycle
- Hot Gas Cycle
- Drip Cycle
- Equalizer Cycle
- Fan Start Delay
|
- Pump Down Cycle
- Pre-Heat Cycle
- Main Electric Defrost Cycle
- Drip Cycle
- Equalizer Cycle
- Fan Start Delay
|
- Pump Down Cycle
- Water Stage1 Cycle
- Main Water Defrost Cycle
|
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Defrost Features
Daily Schedules.
The control has three unique defrost schedules: Weekday (Monday - Friday), Saturday and Sunday.
Automatically adjusts time for daylight savings.
The WEC Multi-Zone Control can be set to automatically change the clock for day light savings or can be set not to change if the
facility is in states where daylight savings is not observed. The Daylight Savings Schedule is set through 2020.
Can schedule up to 8 defrost cycles per day.
The WEC Multi-Zone Control can be programmed to run up to 8 defrost cycles
per day. The control will automatically space out each
cycle evenly or allow the user to program the start
times.
Gas, Electric, Water, or Air defrosts.
The WEC Multi-Zone can operate defrost circuits that are either Off-time, Hot Gas, or Electric. Steps that are not used can be set to 0 minutes, and the controller will skip over them to the next step.
Demand Defrost - Liquid Line Solenoid Feed Time.
The WEC Multi-Zone Control can initiate its defrost cycles base upon the total liquid feed time. This option can be used to activate the system only when the "Number of Cycles per Day" set to zero. The liquid demand delay can range from 0 to 24 hours, in fifteen minute increments.
Demand Defrost - Remote Activation
The WEC Multi-Zone Control has a digital input that forces the control into the defrost cycle. This input can be used to activate the system for an additional defrost cycle, or with the " Number of Cycles per Day" set to zero, the input can be wired to a gang defrost clock and a number of WEC Multi-Zone Control can be staged evenly or to a frost sensor and the WEC Multi-Zone Control will defrost only when necessary.
Defrost Termination
Any one of the following functions will terminate the Main Defrost Cycle:
Clicks-On Thermodisk (Dry Contact).
By providing a closure across the Defrost Termination input terminal, the WEC will terminate the Defrost
Cycle. The Clicks-On should be mounted on the coil and should have a temperature rating corresponding to cleared coil temperature.
Suction Pressure Switch (Dry Contact).
By providing a closure across the Defrost Termination input terminal, the WEC Multi-Zone Control will terminate the Defrost
Cycle. The pressure switch should be mounted on the suction line and should be set to a suction pressure
corresponding to a cleared coil.
Termination Temperature Sensor. The WEC Multi-Zone Control will monitor a temperature sensor mounted in the coil. The WEC will terminate the Defrost Cycle when the
temperature exceeds a selectable Termination Setpoint.
Time.
If the WEC does not detect a termination signal, the Main Defrost Cycle will terminate at the end of the programmed cycle duration.
Defrost Termination Log. The WEC has a "Defrost Log" that records the duration of the previous 10 defrost cycle Defrost stages. This log can
be used to determine whether the current defrost setup is operating efficiently or whether adjustments need
to be made
Temperature Control
Each WEC Multi-Zone Control comes with a temperature sensor for monitoring or controlling the temperature in the refrigerated room.
The control monitors for both high and low alarms each having its own programmed delay when programmed. The WEC will maintain the space temperature by cycling the LLS
based upon a Temperature Setpoint and a plus/minus differential. The WEC will open the LLS when the
temperature reaches T = Setpoint minus Differential Value. The WEC will close the LLS when the temperature
reaches T = Setpoint plus Differential Value.
Fan Cycling -- The WEC can cycle the evaporator
fans once the temperature within the space is met. The WEC will also restart the fans after a setable delay to
prevent stratification of the air.
Temperature Alarming
The WEC can monitor three independent temperature
sensors, the Temperature Control Sensor, the Defrost
Termination Sensor, and an Auxiliary Temperature Sensor.
Temperature Control Sensor -- This sensor
consists of the the sensor used by the WEC for
temperature control. All alarming is disabled during
defrost. Once the WEC controller returns to normal
refrigeration, the alarm delays will begin as if the
sensor has just exceeded the alarm conditions.
Auxiliary Temperature Sensor -- This sensor is
an additional temperature sensor that is monitored and
logged, it does not control any WEC processes other
than alarming. The user can choose whether the alarms
are disabled during defrost or if the alarms are
active during defrost.
Defrost Termination Sensor -- This sensor
consists of the sensor used by the WEC to terminate
the defrost cycle based upon the coil temperature.
Should this temperature read above the setpoint level
of the termination setpoint for over 30 minutes, the WEC will activate its systems alarms.
The WEC will activate its "System Alarm" relays when the
space temperature exceeds the Hi Temp Alarm Limit for a
duration longer than the Hi Alarm Delay or when the
space temperature goes below the Lo Temp Alarm Limit for
a duration longer than the Lo Alarm Delay. The WEC will
activate the System Alarm Relay based upon the following
alarm conditions:
High Alarm . The space temperature must exceed
the High Alarm Limit for a time period longer than the
Hi Alarm delay. This function shall activate the
control's "System Alarm Relay 2".
Low Alarm . The space temperature must be
below the Low Alarm Limit for a time period longer
than the Low Alarm delay. This function shall activate
the control's "System Alarm Relay 1".
Termination Temperature High Alarm. The WEC will activate alarms if the termination Click-On or
the Termination Temperature does not recover within 30
minutes. This function shall activate the control's
"System Alarm Relay 2".
Load Shedding
With the high costs of electricity and the requirements
for reducing energy usage during periods of high demand,
many companies are looking for assistance with their
load curtailment programs.
Some utilities are setting up Demand Response and Load
Curtailment programs to compensate energy consumers for
temporarily reducing their demand for power. Consumers
reduce loads by shutting off equipment or adjusting
their operations to reduce energy usage.
The WEC Evaporator Control System can allow the user to
change the Temperature Control Setpoint to a higher
value in order to reduce energy demand.
Load Shedding Initiating Methods:
1) Dry Contact Closure - The WEC has a dry contact input for Load Shedding
Operation. This input can be connected to a Load
Monitor, a Current Switch to activate the Load Shedding
routine when the facility approaches a high demand
levels, or a manual switch.
2) Manually Forced - The WEC will operate
in the Load Shedding mode if forced in the control
software.
3) Daily Schedule - If activated, the WEC will go into Load Shedding at the same time daily.
4) Gencom Communications Interface - The WEC Control Panels can be placed into Load Shedding via
Gencom Communications System.
Shutdown (Standby)
Some refrigerated facilities need to be placed into Shutdown or Standby at certain times, whether they are a
seasonal facility (i.e. only stores produce during the harvest season), require maintenance or cleaning, or a
production room where the room is not used during the overnight hours.
Load Shedding Initiating Methods:
1) Dry Contact
Closure - The WEC has a dry contact input for
Standby (Shutdown) Operation.
2) Manually Forced - The WEC will shutdown operations forced in the control software.
3) Daily Schedule - If activated, the WEC will
go into Standby at the same time daily.
4) Gencom Communications Interface - The WEC Control Panels can be placed into Standby via Gencom
Communications System.
Additional options include:
1) Fans Run During Standby - The option of whether to shut off the fans when the
evaporator is shutdown.
Remote Communications
GenCom Communications allows the computer operator to access the controllers within a facility via a PC. All control programming and logging functions are accessible and can be set or changed from the computer. The user can view all text and data logs, make programming changes to the controller, initiate defrost cycles, and investigate alarm conditions.
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