14
User
Guide RS8KH202 © Danfoss 2019-03
AK-PC
572
Receiver
Rec. control status
Receiver status
Control status
Here you can see the status of the receiver controller:
Prec
Off / Idle / Emergency / Normal / Hot gas dump
Prec reference
Here you can see the receiver pressure
Vrec OD
Here you can see the reference point for the receiver pressure
Hot gas dump
Here you can see the opening degree of the valve Vrec in %
Rec. control settings
Here you can see the status of the valve for hot gas dumping
Control mode
Controller type
The controller is normally set to "Auto" but can be changed to "Manual".
MAN / AUTO
Fac: AUTO
Vrec manual capacity
When setting to "Manual", capacity can then be forced set in %.
Min: 0 %
Max: 100%
Prec max.
Here the maximum receiver pressure can be configured
Min: 34 bar
Max: 89 bar
Fac: 59 bar
Easy PI select
Set how quickly the PI regulation must react here: 1 = slowly, 10 = very quickly.
(For setting 0 "User def." the special settings options will open. Kp, Tn. These options are only for
trained staff.)
Min: 0 (User def.)
Max: 10
Fac: 5
Kp
The reinforcement factor for the PI controller (can only be viewed and configured when the
previous menu has been set to "0")
If the Kp value is lowered, regulation runs more smoothly
Min: 0,5
Max: 10
Fac: 2,0
Tn
Integration time for PI regulation (see above)
If the Tn value is increased, regulation will run more smoothly
Min: 30
Max: 300
Fac: 75
Manual hot gas
Here you can override the hot gas valve.
(Only if hot gas dump is defined in the AUX section)
Auto
Man on
Man off
Oil Control
Limitation
It is only possible to use oil management if the solid state outputs (DO5 and DO6) are free.
If regulating using compressor type Bitzer CRII, the two outputs will be used by the compres-
sor and oil management cannot be performed.
DO-demand
Control type
Adjust whether oil management will be used.
You can choose whether pulse controls run only with a timer function or whether pulse
controls are performed only when there is a signal from a level switch
Non / Timer only /
Niveau
Fac: Non
Oil control status
Here you can see the oil management status:
None / Main switch off / Idle / Valve open / Delay before next pulse
Oil cycle time
Adjust the period between pulses. (Only if regulated with the "Timer only" setting)
Min: 180 s
Max: 1800 s
Fac: 300 s
Oil pulse duration
Adjust the valve opening time for each pulse
Min: 1 s
Max: 30 s
Fac: 5 s
Safety monitoring
PoMT Min. limit
Safety limits for min. PoMT
If a low value is registered, all compressors will cut out
Min: -55°C
Max: 30°C
Fac: -40°C
PoMT Max. alarm
Alarm limit for high PoMT
If a high value is registered, an alarm will be generated
If a higher value is registered during a load limitation, the load limitation will be cancelled
until Po has returned to the reference.
Min: -30°C
Max: 30°C
Fac: 5°C
Superheat Min. MT
Alarm limit for insufficient superheating
(Superheating is measured in the suction line by PoMT and SsMT.)
Min: 0 K
Max: 20 K
Fac: 4 K
Superheat Max. MT
Alarm limit for excess superheating
Min: 20 K
Max: 80 K
Fac: 50 K