What to check

The CISA electric lock have a magnetic coil in them which needs 12volts 1-2Amps.

This high current combined with a long cable run can cause too much volt drop. Our Video systems all have a lock relay in them, but our Audio systems do not.

Corrective Action

So in all cases keep the power unit within 10 metres of the door and for Audio fit an interface relay to bypass volt-drop to the phones and/or increase the AC output from 12v AC to 18v AC,

Additional notes

GPRU

Links

https://www.entryphone.co.uk/shop/productdetail/GPRU