6.3.2
Testing the brake in accordance with EN 81-20:2020
"
"
To test only the e
ff
ect of the brake, the short-circuit of the motor windings, if installed, must be
disabled.
"
"
For the test, the cabin should be positioned in the centre of the shaft.
1. Overload
"
"
The test shall be carried out whilst the car is descending at rated speed with 125 % of the rated
load and interrupting the supply to the motor and the brake.
"
"
If the elevator machine is driven upwards with a load of 125 %, approx. 2.5 x more losses occur
than with a 100 % load, which accordingly leads to a rapid heating of the motor. As there is no
switch-o
ff
in case of overheating during travel, a trip may only be of short duration.
ZAtop SM132/ZAtopx BD132: maximum 10 seconds
ZAtop SM180/ZAdisc SL506/ZAdisc SL510: maximum 15 seconds
ZAtop SM190/SM200/SM210/SM225/SM250/SM315: maximum 20 seconds
ZAsyn2 500AL/ZAsyn 700AL/ZAsyn 860AL: maximum 20 seconds
"
"
Longer travel at 125 % nominal load due to a low inspection speed and/or a high travel distance is
not permitted.
"
"
To avoid this problem, we recommend transporting the test load upwards in 2 parts and with a
125 % load only downwards.
2. Failure of one brake circuit:
"
"
The test shall be carried out whilst the car is descending at rated speed with rated load.
"
"
To simulate failure of a brake circuit, it must be possible to keep the brake circuits open mechan-
ically independently of one another even when opening the safety circuit.
"
"
This condition may not be permanent and must therefore be created using buttons or similar.
"
"
At the same time, the safety circuit should be opened when using this function.
"
"
For this test, the elevator must be observed.
"
"
If no discernible delay occurs, the brake circuit held open is to be closed immediately.
"
"
The system should be stopped and the brake tested.
As an example, refer to the principle circuit diagram in the
“
Electrical installation / Brake / Brake
control
”
chapter. The logic of the principle circuit diagram should be understood. Transferability to the
relevant application must be veri
fi
ed and ZIEHL-ABEGG SE provides no guarantee of suitability.
If the circuit is designed in accordance with the principle circuit diagram:
"
"
At the nominal speed, press one of the buttons and hold it down until the elevator has stopped.
"
"
Repeat the test with the other buttons to test the other two brake circuits.
3. Testing the inductive proximity switches
"
"
The release monitoring for the brakes must be evaluated.
"
"
Before every trip, the change in the state of both brake circuits must be monitored separately.
"
"
Switching must thus be tested individually, according to the function as an NC and/or NO contact.
"
"
If there is a missing or incorrect signal, the elevator cabin may not leave the stopping point.
6.4
Pull out of safety gear
If the cabin loaded with rated load is caught by the trap due to a failure or during the acceptance
inspection, the capture device could be very tight. In this case it is quite possible that the elevator
machine torque is insu
ffi
cient to pull the cabin out of the trap.
With gearless elevator machines in the shaft, the elevator machine is usually not accessible. A
handwheel is unnecessary in such a layout.
With gearless elevator machines in machine rooms, a handwheel does not make any sense because
there is no gear reduction. That is because due to the low moment arm of force, only slight force can
be applied. A handwheel could even present a hazard, as even with only a slight imbalance in the
installation, it is no longer possible to stop the elevator with the handwheel.
For both cases involving gearless elevator machines:
"
"
If the elevator machine torque or the traction conditions are not su
ffi
cient, a block and tackle or
similar device should be used.
"
"
Suitable block and tackle should be provided.
Original operating instructions
ZAtop
–
model series SM315.100A
Commissioning
A-TBA22_02-GB 2022/50 Index 002 Part.-No. 01013486-GB (EU-BD 1075)
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