New lift FST-2XTs, Manual

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Replacing FST-2s with FST-2XTs
Appendix
32 ManualforreplacingFST-2swithFST-2XTs
FST-2XTs 51 00 – Remarks

FSM 5 20 – Remarks
Safety circuit on the printed circuit board
The switching elements of the safety circuit on the car roof are directly connected to the so-called car
top control module (abbreviated FSM). The two assemblies FST-2XTs 51 00 and FSM 5 20 are linked
via the travelling cable to form a unit and are interdependent of one another. On the car top control
module, the safety circuit with conductor paths is fed between the connection terminals and the
travelling cable plug. The conductor paths of the safety-relevant circuits on the printed circuit board
have a distance from each other of at least 4 mm on the outer layers. Where not technically possible,
this is achieved by means of an additional air gap on the printed circuit board. According to IEC 664-1,
this corresponds to pollution degree 3. Because these conductor paths are designed for a nominal
current of 4A, use a fuse of max. 4A for the safety circuit.
 Function and test description of the safety circuit bypass control for the door
bypass in the zone
Figure 1
1. The actual safety circuit bypass control consists of the K21, K22 and K23 safety relays.
2. A zone release (+24V) must be activated by the controller. A zone release is active if necessary,
i.e., if the controller is to open the car door on the corresponding floor.
3. First, K21 must be energized; for this purpose K20, K22 and K23 must be de-energized. K21
holds itself as long as K20 is not energized and there is a zone release.
4. K23 can only be energized after K21 if zone switch B closes. K23 holds itself as long as zone
switch B is closed.
5. K22 can be energized after K23 and K21 if zone switch A closes. K22 holds itself as long as zone
switch A is closed.
For the next test step, see page 3
Page 2 of 3 Edition: 23.09.2014