Fri-Jado BS10i, Service Manual

Page: 30 / 88

Electrical tests
Page 30
Service Manual Bake Star intelligent
PKII
form 9123665 rev. 06/2013
The electric door lock consists of the follo-
wing parts:
a) An electro-magnetic coil to open the door.
b) A micro switch to detect the open/close
position of the door and feedback a sig-
nal to the processor..
c) A black plastic housing with mechanical
parts including an emergency (manual)
opening lever.
d) The door catch “fork”.
Working principle.
The electro-magnetic coil is designed for
24VDC. This voltage however, may only be
applied for a few seconds, otherwise the
coil will burn out. For this reason, the coil
is activated by discharging a capacitor. As
soon as the capacitor (4700uF) is empty,
the current is dropped down to zero.
The capacitor needs some time to recharge.
Pushing the door switch in short periods
after the other has therefore no use. It
will result in soft “clicks” without opening
the door. In 5 seconds, the capacitor will
be charged. The coil is connected with the
blue wires.
The micro switch gives the “door open” or
“door closed” signal. The connection is as
follows:
When the door is closed, black is connected
with grey. The switch is NOT activated in
this case.
When the door is opened, black is disconnec-
ted from the grey wire.
The brown wire signal is not used on the
board.
Tip:
For test purposes, an old plug from the door-
lock can be used.
Cut the blue wires and the brown wire.
Strip the black and grey wire and connect
them together.
When this plug is pushed into the socket
of the board, it gives the “door closed”
signal.
THE ELECTRIC DOORLOCK
Microswitch
emergency lever
Coil (4,75 Ω)
Lock closed
Lock opened
Lock closed
Test plug
Lock opened
Switch activated