Troubleshooting
4.2
Faults of the heating system
Temperature of inner chamber does not in-
crease to set temperature
Controller regularly displays the operating
parameters
Setting of safety controller MB1 I/O-board ex-
ceeded?
Yes
Operating error (see operating manual)
No
Optional class3.1 overtemperature set too low?
Yes
Operating error (see operating manual)
No
Solid state relay (-
4K1
) of heating defective?
Yes
Replace solid state relay (chap. 8.6,
page 82)
No
Controller MB1 I/O-board (
-3N2
) defective?
The binary outputs BA 4, heating element, and
BA 6, safety controller (0 – 5 V DC) are non-
functional.
Yes
Replace controller MB1 I/O-board (chap.
8.8.1, page 85)
No
Solid state relay (-
5K1
) for safety controller de-
fective?
Yes
Replace solid state relay (chap. 8.6,
page 82)
No
Power relay (
-5K2
) defective?
Yes
Replace power relay
(chap. 8.6, page 82)
No
Heating element (
-4E1
) defective?
Yes
Replace heating element
(chap. 7.8, page 66)
At the binary output BA 4 of the controller MB1 I/O-board (
-3N2
) there must be a voltage
of +5 V DC. At the same time, the safety controller output BA 6 on the controller MB1
I/O-board must put out a voltage of +5 V DC. The solid state relays (-
4K2
) and (-
5K1
)
and the power relay (-
5K2
) must have picked up.
Service Manual KBF (E5.2) 04-2015
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