Siemens MOBILETT Plus Manual page 31

Turn-plate control
MOBILETT Plus only
The block diagrams and the wiring diagram X037E, sheet 170 are the basis for the func-
tional description given below.
The turn-plate control circuit includes the boards D8, D1 and D4 and the turn-plate sole-
noid PM.
The turn-plate solenoid is controlled with the two signals "PIVOT ON" and "PIVOT HOLD".
It is possible to measure both signals on board D4.
Pressing one of the buttons activates the control signal "PIVOT ON", and a lamp lights up
in both control buttons.
Turn-plate solenoid switch-off also takes place by activating one of the two control but-
tons, then the lamps in the buttons are turned off.
The signal "PIVOT ON" controls the relay MR1 on board D4, switching an AC voltage
from board D8 to a rectifier on board D4.
This supplies the turn-plate solenoid coil with a voltage of about 23.5 V DC. A relatively
high current surge of about 20 A results. This in turn activates the turn plate solenoid.
By means of a system of levers and springs the resulting magnetic force presses the turn
plate, located beneath the carriage unit, against the floor.
In order to reduce the current drawn from the power line without letting the system of
levers and springs fall back into its starting position the microprocessor on the CPU board
D1 switches off the signal "PIVOT ON" and switches on the signal "PIVOT HOLD".
The contact in relay MR1 then returns to its original position and the contact in relay MR2
is switched on.
Siemens-Elema AB
Solna, Sweden
The turn plate can be controlled by either one of the two turn-plate buttons,
located at the left and right sides of the vertical column.
Register 6 SPR8-215.850.02
Rev. 01 01.02
10
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