5. Operation
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104781 - MRF-2 | MRH-2 - V2.4 - 22.07.2020
5.2 Controller overview
F2
K3
K4
K1
K2
F1
L N
RS485
Relay outputs
For directly controlling control contactors
(pumps, compressors, heaters, etc.)
'Compressor rotation' or 'hot gas bypass' pro-
grammable.
High-pressure monitor: Functional safety en-
sured even in the event of a microprocessor
fault (meeting legal requirements.)
Timer module:
Various delays can be confi-
gured using the built-in ti-
mers.
For example:
Delayed switch-on after
mains power on,
Mutual delays between re-
lays
Compressor protection
Digital inputs:
Monitoring of external sys-
tem components.
Error message via LED and
relay output.
Internal logic operation with
timer module.
Analogue input:
either as a current input (4-
20 mA) or a voltage input (0-
10 V) can be parameterized.
Analogue output:
either as a current output (4-20
mA) or voltage output (0-10 V)
can be parameterized.
Universal
sensor inputs:
Operation with up to three
sensors.
Inputs configurable for
PTC, PT-100 2- or 3-wire
or PT 1000
RS485 interface:
for connection to the PC
Controller example
Digital
inputs
Power supply:
Variant A: 230 V ~
Variant F: 24 V -/=
