Protection Features - Danfoss EKE 1A User Manual

Superheat controller, Type EKE 1A, 1B, 1C, 1D
Table 35: Start OD without protection
Parameter
N102
N105
N017
Defrost sequence
Defrost Sequence must be initiated by the master controller. In a standalone configuration, the defrost mode is not
possible.
To initiate defrost, the system mode is changed from Heat pump to A/C, hereby the outdoor unit will act as a
condenser and the hot discharge gas from the compressor will defrost the coil. In some system electrical heaters are
used instead of reversible system but defrost sequence can still be used.
Figure 76: Defrost sequence
Injection
OD %
Defrost start
signal received
Defrost OD
Defrost
end OD
0
Defrost start time
The user sets the Defrost OD, the Defrost end OD, defrost start and end time (see table below).
The defrost start/end commands are received from one of the following options:
1. Modbus register (nonvolatile memory) – default OFF at power-up
2. DI's for use as defrost start/stop. Only one DI can be assigned for defrost start/stop. Start is defined as a transition
from off to on, a transition from on to off is a stop signal.
Table 36: Defrost Sequence parameters
Parameter
D101
D102
D100
D104
D103
D105

6.3.2 Protection features

EKE 1x series has protection features that prevents the system from operating under bad conditions, these
protection features are:
© Danfoss | Climate Solutions | 2022.06
Function
Startup mode
Startup time
Startup OD
Defrost Defrost end
Defrost end
signal received
Defrost end
closed time
Function
Defrost start low pressure limit
Defrost start time
Defrost OD
Defrost end closed time
Defrost end OD time
Defrost end OD
Description
2 = Minimum OD without protection
Min value: 1 second | Max value: 600 seconds
After startup time the Startup OD is Disabled, and controller will switch to the set control mode.
Starting OD degree of the valve.
Startup
time
Defrost end
OD time
Description
The defrost sequence starts by closing
the valve, which is kept closed until the
'D101 Defrost start low pressure limit' is
reached or D102 'Defrost start time' is
exceeded.
 WARNING:
This parameter is valid only if the de-
frost start time >0
The defrost sequence starts by closing
the valve, which is kept closed until the
'D102 'Defrost start time' is exceeded or
'D101 Defrost start low pressure limit' is
reached
Sets the valve opening degree after the
Defrost start time is passed.
After the defrost stop signal, the valve
closes and will open again after 'Defrost
end closed time' is exceeded
End of the defrost, start of the startup
mode.
Sets the valve opening degree after De-
frost end closed time.
BC398828796060en-000101 | 52
Default
1.0 brag
0 s
0%
1s
1s
50%