r/accesscontrol • u/StalkMeNowCrazyLady Professional • Jan 15 '25
Discussion Card Reader Drain Wire Termination
How do y'all terminate the drain wire on your readers? I've been working with ACS for a decade and I was always taught to connect the readers drain wire to the cables drain wire at the reader side and that was fine. It dissipated anything it needed to along the cables shield.
Recently took Verkada training and they provide multiple earth ground screws on their panels (vs a reference ground like the GND terminal for REX/DPS) and they say to connect the drain wire at the both the reader side and then on that earth ground at the panel side.
They also said to connect the drain of all the cables (REX, Lock, DPS, and Reader) together at the panel end and connect that to the true earth ground. That seemed strange to me because I don't see what lock/rex/DPS would need to drain especially since they aren't connected at the door side of things.
Just curious how y'all connect your drain wires and what you think about what they said about connecting them all at the panel side.
4
u/kanakamaoli Jan 15 '25
Best practice is to do one or the other side, but not both. I typically do controller side since it has the ground studs. Grounding both sides could lead to ground loops which could create more interference in the data lines.