Operating Principle; Temperature Sensor Ntc; Burner Control Device T P810 - Dometic RM 8401 Service Instructions Manual

Components

2.1.5 Operating principle

The electronics regulates the function of the
components according to the selected energy,
e.g. power supply for the heating elements. In
addition the AES-power module ensures the
operating with the optimal energy source accor-
ding to the priority "230V AC - 12V DC - GAS".
It also controlles the low voltage operation at
230V AC (no low voltage op. at 12V DC mode),
and the "refuelling stop function" as well. The
temperature sensor and interior light are also
controlled by the electronics. The power modu-
le is protected with 1A fuse for 12 VDC.
No low-voltage-control during 12V mode at
RMD-models.
Differences power module RMD 8xxx to
RM 8xxx
Controls are hidden behind the door; integra-
ted between freezer and cooling compart-
ment. Status is shown by blue LED (fridge
working) and red LED (error).
In Auto Mode "AES" is shown on the display
(instead of "AU").
No electrical doorlock available.
Frame heater activation via right button.
Automatic switch off of the frame heater after
2 hours.
Acoustic alarm limited to 1 minute, but
repeated every hour (if error has not been
reseted)
Powermodul mounted on the lower back.
Access via lower ventilation grid.
The functionality of RMD 8xxx models will
also be valid for RM 8xx1 and RM 8xx5
models probably starting with season 2010.
2.2

Temperature sensor NTC

NTC - table of resistances
Temperature °C
0
5
10
15
20
25
Measuring points:
electronics / power module
loosen contacts X108
cable white / brown
In case of a defective sensor, the fridge operates in
intervalls (45 min. ON; 14 min OFF).
2.3 Burner Control device P810
activates ignition
flame control and flame failure device
controles gas valve ( closes valve if failure oc
cure)
Power supply : ca. 1.5 V ( only measurable if no
failure exists)
Measuring points : Flat plug
7 6
- +
= 1.5 VDC
14
Resistance in kOhm
27.70
22.29
18.07
14.74
12.11
10.00
between Pin 6 and Pin 7
8
1
Fig. 21