Content → Hardware → GCA

• The GCA modules

8 individual inputs, commanding 8 individual outputs

600 mA max load per output.

Max 42 Volt per output.

8 individual inputs.

Time selection for output duration.

Outputs are activated one by one for power reduction.

Controlling a LGB 1201, Kato or Fulgurex turnout-drive, in fact also some type of Hoffmann turnout motors, only have one coil or motor, that needs to be controlled by polarity.
Even the Bohler WA2 is very nicely useable with this interface.
The normal driver like GCA77 is not suitable for that.
The complexity of this unit is slightly higher.
In the GCA units, it is standard, to separate the power, needed to activate the coils and the LocoNet system by means of optocouplers.
This unit is able to control 8 turnouts, and need 8 inputs from the GCA50.
So 2 units, capable of a total of 16 turnouts, are commanded by 1 GCA50.
It is also possible to use a switch for direct activation without GCA50.
You will need a 5-12Vdc to activate the opto-couplers.
The software in the PIC16F62x is made in such a way that the processor provides a correct timing for the coil, and switch it off after the chosen time.
This will take care that the turnout coil will not be overheated by too long powering.
The time selection is done with the Dipswitch.
The processor in the circuit needs 8 inputs and 16 outputs, and 3 extra for dip-switch reading.
The smaller PIC processors have only maximum 16 I/O.
Therefore I used I2C expanders , making a small processor suitable.\\

refer to: **Connection interfaces**

program files

SW1 is used to set the delay time after which the output will be swotched off.

Inputs, if activated, should remain activated, to keep motor/coil in the chosen position.

GCA50 should be programmed as switch, with C2 NOT checked.

Checking C2 will inverse action.