# Third-Party Wireless Locks

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This guide offers best practices for convenience, but RS-485 devices should ultimately be installed according to the [TIA/EIA-485-A](https://store.accuristech.com/tia/standards/tia-tia-485-a?product_id=2591400) standard.
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### Before you begin

Verkada’s third-party wireless lock integrations that involve wiring hubs or locks to an access control panel via RS-485, covered in this article, include:

* PIM400-485 hubs for AD400 locks
* AD300 locks
* GWE hubs for Engage Online locks
* AH30 hubs for Aperio locks

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## Best practices

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**Terminate the shield drain at the panel side only, and connect it to earth ground.**
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**Use RS-485 approved cabling; Belden 9841, 9842, or equivalents are recommended.**
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**Connect the RS-485 signal ground to the negative terminal of the power supply.**
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**Keep unshielded wiring at the panel or device to less than two inches in length.**
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**Run power and data in separate cable jackets if they follow the same path.**
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**Verify that each lock or hub is receiving adequate power per its specifications.**

* Typically, one Verkada reader port powers one device.
* For additional devices, use separate reader ports or an external power supply.
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## Wire multiple RS-485 devices to a panel

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**Daisy-chain data between devices in a linear bus topology. Avoid star topologies.**
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Do not use T-taps on data lines.
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**Connect shield drain wires between cables, but terminate the drain only at the panel.**
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**Ensure each device receives adequate power, accounting for the total load on the power supply.**
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Do not daisy-chain power from a Verkada panel door port.
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**Maintain a continuous signal ground across all devices, connected to each power supply’s negative terminal.**
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