Emerson Dixell XC645D User Manual

1592001830 XC645D GB r3.4 04.09.2017.docx XC645D 38/50
19.3.1 Suction Superheat detecting
To detect the suction
superheat an auxiliary
probe among P3 (term.
38-42) or P4 (term. 22-
23) has to be set as
superheat temperature
probe.
To do this set ASH9 = P3
or P4.
Controller automatically
calculates the suction
superheat using the
value of the suction
probe P1 and the probe
set in the parameter
ASH9.
The SH is available after
1 minute since at least
one compressor is running.
19.3.2 Low superheat signalling and actions
Controller can signal low superheat pre-alarm, only warning, and low superheat alarm, warning
and regulation according to parameter ASH4.
The alarm messages and the regulation are described in the following table
Label
Meaning
Cause
Action
Recovery
PrSH
Low
superheat
Pre-allarm
The superheat is less
than: SH< ASH2 +
ASH0 for ASH1 time
Only warning
Automatic:
when superheat:
SH>ASH0+ASH2+1°C(2°F)
ALSH
Low
superheat
allarm
The superheat is less
than: SH< ASH2 for
ASH3 time
Regulation depends on ASH4:
ASH4 = no: regulation not affected.
ASH4 = yes: regulation is stopped.
Automatic:
when superheat:
SH> ASH5 + ASH2
19.4 Hot gas injection valve
Controller can manage a hot gas injection valve to increase suction superheat. See above figure.
19.4.1 Parameters
A relay must be set as hot gas valve: oA2 or oA3 or oA4 = HGi, and
an auxiliary probe among P3 (term. 38-42) or P4 (term. 22-23) has to be set as superheat
temperature probe ASH9 = P3 or P4.
Then the following parameters:
ASH7 Superheat value to enable hot gas injecting valve (0.1 to 15.0°C/ 1 to 30°F)
ASH8 Differential for ASH7 (0.1 to 30.0°C/ 1 to 60°F)
19.4.2 Regulation:
The regulation respects the following schema:
Superheat < ASH7 – ASH8  HGi on
Superheat > ASH7  HGi off

Emerson Dixell XC645D Specifications

General

Brand	Emerson
Model	Dixell XC645D
Category	Controller
Language	English