MODBUS Termination Blocks
Default Parameter Map • 47
LOP
0
Minimum operating
pressure threshold
and valve opening
of
dML
value
PA4 to MOP
If the suction pressure exceeds the
minimum operating pressure value, the
device will signal this situation
generating the
LOP
alarm (according to
PrU
parameter).
dML
30
Delta
[MOP - LOP]
0 to 100%
Until the
MOP
alarm is active, the
valve will close, every second, of a
value equal to the
dML
percentage.
Until the
LOP
alarm is active, the valve
will open, every second, to a value
equal to the
dML
percentage.
MSH
144
Maximum
superheat alarm
threshold
[LSH to 144°F]
[LSH to 80.0°C]
If the superheat value exceeds
MSH
value, the display will show the
MSH
message until the delay time
SHd
expires.
LSH
3
Minimum
superheat alarm
threshold
[0°F to MSH]
[0.0°C to MSH]
If the superheat value is lower than
LSH
during the
SHd
delay time, then
the display will show the message
LSH
.
As soon as the superheat value is
lower than LSH value, the valve will
close immediately, without waiting
the SHd delay time (to avoid
evaporator flooding).
SHY
1
Hysteresis for
superheat alarm
recovery
[MSH – SHY]
and
[LSH + SHY]
[1°F to 45°F]
[0.1°C to 25.5°C]
-
SHd
0.0
Delay of superheat
alarm signaling
0.0 to 42min00sec (252)
If a superheat alarm occurs, the delay
time
SHd
expires before the controller
shows an alarm.
Format
: min.10sec
Resolution
: 10sec
FrC
0
Integration additive
constant
(Fast-recovery)
0 to 100s
It permits to decrease faster the integral
action when
SH
value is below the
setpoint. With higher values the valve
closes faster. If
[FrC = 0]
fast recovery
function is disabled.
Sub
10
Number of pressure
values used to
calculate the
average pressure
0 to 100
It uses the last average values of the
pressure to calculate the superheat.
SLb
0
Reaction Time
0 to 255s
0 = controller calculates automatically
the time to update the valve position.
1 to 255s = controller updates valve
position every SLb seconds
tEP
nU
Predefined valve
selection
nU to 10
nU
= manual setting
See
Section 6.4.,
Valve Connections
and Configuration
Label
Value
Description
Range
Notes
Table 24-1
- Default Parameter Map
Содержание XM678D
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