
Operating instructions
EXD-TEVI Economizer Controller with
ModBus Communication Capability
Emerson Climate Technologies GmbH www.emersonclimate.eu 2/3
Holzhauser Straße 180 I 13509 Berlin I Germany Date: 19.08.2014 EXD-TEVI_OI_EN_R02_865908.docx
Preparation for Start-up:
•
Vacuum the entire refrigeration circuit.
•EMERSON’s Electrical Control Valves EXM/EXL are delivered in partially
open position. Do not charge system with refrigerant before closure of valve.
Procedure for Valve Closure:
•
Apply supply voltage 24V to EXD-TEVI while the digital inputs (DI1 and DI2)
are Off (open). The valve(s) will be driven to close position.
•
After closure of valve, start to charge the system with refrigerant.
Setup of parameters
(need to be checked/modified before start-up):
•
Make sure that digital inputs (DI1 and DI2) are off (open).
Turn the power supply ON.
Once the main parameters have been selected/saved the EXD-TEVI is ready for
startup. All other parameters can be modified at any time during operation or
standby if it is necessary.
Procedure for parameter modification:
The parameters can be accessed via the 4-button keypad. The configuration
parameters are protected by a numerical password. The default password is “12”.
To select the parameter configuration:
•
Press the button for more than 5 seconds
•
A flashing “0” is displayed
•
Press until “12” is displayed; (password)
•
Press to confirm password
•
The 1
st
parameter H5 is displayed
•
Press or to show the code of the parameter that has to be changed
•
Press to display the selected parameter value
•
Press or to increase or decrease the value
•
Press to temporarily confirm the new value and display its code
•
Repeat the procedure from the beginning "press or to show..."
To exit and save the new settings:
•Press to confirm the new values and exit the parameters modification
procedure.
•To exit without modifying/saving any parameters. do not press any button for at
least 60 seconds (TIME OUT).
Reset all parameters to factory setting:
•
Make sure that digital inputs (DI1/DI2) are Off (open).
•
Press and together for more than 5 seconds.
•
A flashing “0” is displayed.
•
Press or until the password is displayed (Factory setting = 12).
If password was changed, select the new password.
•
Press to confirm password
•
Factory setting are applied
Display System Parameters:
•
In standard mode the EVI superheat is shown at the display. In case of wet vapor
injection and economizer function this changes to discharge temperature.
•
To display other data of EXD-TEVI:
•
Press for 3 seconds to show data
To display data: Press the button for 1 second until index number according
to the below table appears. Release the button and the next variable data will
appear. By repeating above procedure, variable data can be displayed in a sequence
as in following table.
Index No. Variable data Units
Source
0 Default displayed value
K measured
1 EVI Pressure bar measured
2 Total combination
Valves opening %
3 EVI suction gas temp °C measured
4 EVI saturation temp. °C calculated
5 Discharge temp. 1 °C measured
6 Discharge temp. 2 °C measured
Note: After 3 minutes, display reverts to index 0.
Manual alarm reset/clearing functional alarms (except
hardware errors):
•
Press and together for 5 seconds.
When the clearing is done, “CL” message appears for 2 seconds.
List of parameters in scrolling sequence by pressing
button:
Code
Parameter description and choices
Min Max Factory
setting
H5 Password 1 1999
12
Adr ModBus address 1 127 1
br Modbus baud rate 0 1 1
PAr Modbus parity 0 1 0
tAn Single / Tandem Operation 1 2 2
1 = single compressor, 2 = tandem compressor
1u4 Superheat control mode 0 2 1
0 = Standard; 1 = Slow;
2 = Fix PID (For trouble shooting/no warranty if system to be
operated with fix PID)
1uu Start valve opening (%) 5 100 15
1u9 Start opening duration (second) 1 30 5
1u5 Superheat set-point (1/10 K) 0.5 30.0 7.0
1PE Economizer control fixed PID (Kp
factor; 1/10) 0.1 10.0 2.0
For trouble shooting/no warranty if system to be operated with PID
1IE Economizer control circuit1 (Ti factor)
1 350 100
For trouble shooting/no warranty if system to be operated with PID
1dE Economizer control circuit1 (Td factor
1/10) 0.1 30.0 1.0
For trouble shooting/no warranty if system to be operated with PID
1uC Units conversion 0 1 0
0 = °C, K, bar; 1 = F, psig
1dt Discharge temperature limit (1/100 °C)
100.0 140.0 135.0
1Lo Load shedding valve offset 10 20 18
(Valve opening change by adding/removing compressors.
10 is no offset, 20 is 50% of current valve opening as offset)
dAd Discharge temp. alarm delay (sec) 10 60 60
EC0
Number of installed expansion valves
1 2 1
t2E Threshold start second valve (%) 0 50 30
Control (valve) start-up behavior (Parameter 1uu and 1u9)
1uu:
Min.: 0% (<1 sec.)
Default: 15% (< 1.5 sec.)
Max.: 100% (< 6 sec.)