Emerson XEV22D Installation And Operation Manual page 21

Code Description
Type of alarm signaled by relay
tdA
Lower pressure limit for super-
LPL
heat regulation
Maximum operating pressure
MOP
threshold
Lowest operating pressure
LOP
Pressure alarm hysteresis
PHY
delta MOP-LOP
dML
Maximum superheat alarm
MSH
Lowest superheat alarm
LSH
Superheat alarm hysteresis
SHy
Superheat alarm activation de-
SHd
lay
Fast-recovery constant
FrC
Local display
Lod
Temperature measurement
CF
units
Pressure measurement units
PMU
Resolution (only °C)
rES
Table 10-1 - List of Parameters
How to Assign a MODBUS Address
(ALL, SH, PrE, di)
ALL = all alarm; SH = superheat alarm; PrE = pressure alarm; di = ac-
tivation only when digital input configured as rL is activated.
(PA4 to P20 bar/ psi)
When the suction pressure comes down to LPL, the regulation is per-
formed with a LPL fixed value for pressure; when the pressure comes
back to LPL, the normal pressure value is used. (related to PrM param-
eter).
(PA4 to P20 bar/ psi)
If the suction pressure exceeds the maximum operating pressure value,
the controller signals a condition with a High Pressure alarm LED (relat-
ed to PrM parameter).
(PA4 to P20 bar/ psi)
If the suction pressure comes down to this value, a low pressure alarm is
signaled with Low Pressure alarm LED (related to PrM parameter).
(0.1 to 5.0 bar/ 1 to 72 PSI)
Alarm hysteresis to disable alarm signaling.
(0 to 100%)
When a MOP alarm occurs, the valve will close at the dML percentage
every one second until the MOP alarm is active. When LOP occurs, the
valve will open at the dML percentage every one second until LOP
alarm is active.
(LSH to 32.0°C/ LSH to 176°F)
When the superheat exceeds this value, a high superheat alarm is sig-
naled after interval SHd.
(0.0 to MSH°C/ 32 to MSH°F)
When the superheat goes down to this value, a low superheat alarm is
signaled after interval SHd.
(0.0 to 25.5°C/ 1 to 77°F)
Hysteresis for superheat alarm deactivation.
(0 to 255 sec)
When a superheat alarm occurs, the time SHd has to pass before signal-
ing alarm.
(0 to 100 sec)
Increases the integral time when SH is below the setpoint. If FrC = 0,
fast-recovery function is disabled.
DISPLAY
Display: (SH, PEr, P1, P2)
SH = superheat; PEr = valve opening percentage; P1 = value of temper-
ature measured; P2 = pressure measured by P2 probe;
(°C to °F)
°C = Celsius degree; °F = Fahrenheit degree
CAUTION! By changing the measurement unit, the regulation parame-
ters have to be changed correctly.
(bAr, PSI)
bAr = bar; PSI = psi
CAUTION! By changing the measurement unit, the regulation parame-
ters have to be changed correctly.
(dE to in)
Whether a whole number or decimal point is used in temperature reading
Function
Parameters • 15