Wiring a Door to an AC41 Cassette
Instructions on wiring a door to an Verkada AC41 cassette
Updated over a week ago

The Verkada AC41 access controller comes with 5 removable cassettes that are designed to make the installation and cabling process quick and easy. Simply remove the cassette, install the necessary wires into the cassette, and plug the cassette back into the AC41.

Before Getting Started

WARNING! – ENSURE POWER IS DISCONNECTED FROM THE AC41 AND LOCKING HARDWARE BEFORE WIRING READERS AND OTHER DEVICES. FAILURE TO DO SO CAN DAMAGE THE AC41.

Wiring fail-secure and fail-safe locking hardware

Be aware of the different ways to configure locking hardware:

  • Fail-secure locks require electrical power to unlock. In their normal unpowered state, they remain locked. They use a NO (Normally Open) circuit. Therefore, when power is interrupted, it will remain locked.

  • Fail-safe locks require electrical power to remain locked. In their normal powered state, they remain locked. They use a NC (Normally Closed) circuit. When power is interrupted, it will unlock.

Keep in mind that some door strikes can be wired as fail-safe and some electromagnetic locks can be fail-secure; always check your third-party locking hardware wiring instructions and ensure you’re using the right configuration for your requirements.

Dry vs Wet

  • Dry - The AC41 does not provide power to the locking hardware (typically used with external power supplies)

  • Wet - The AC41 provides 12V or 24V power to the locking hardware

Best practice: Always use an external access power controller (Dry setup) when wiring up an ELECTROMAGNETIC lock (maglock).

Wiring Process

Remove the cassette

Begin by removing a door cassette from the AC41 by lifting it from the side tabs. This will make wiring a breeze.

Note: Before you begin wiring your doors, please see the recommended wires for the AC41.

Connect the Lock (Access Power Controller - Dry Contact)

When using an access power controller (APC) which uses a dry contact, ensure that NONE is selected on the door power selection switch. The APC will detect if the AC41 relay is open or closed and translate that to the lock. Maglocks, crash bars, gates almost always will be wired in using an access power controller.

Fail Secure

Fail Safe

Note: When the AC41 door power selection switch is set to None, the relay is not completely dry. The AC41 has the ability to power locks at 12V or 24V but as a result, our relay is not completely dry. Isolation or common ground issues may occur.

Connect the Lock (Wet)

In a wet configuration, ensure that power selection for each door is set to the correct voltage as outlined by the locking hardware specifications.

  • Set it to 12VDC for 12-volt locking hardware

  • Set it to 24VDC for 24-volt locking hardware

The AC41 is rated to power 12V locks up to 700mA and 24V locks up to 350mA.

Wet 12V / 24V NO-COM

If you have a fail-secure lock, connect to NO-COM where LOCK ( + ) positive goes into NO (fail secure) and LOCK ( – ) goes into COM.

Wet 12V / 24V NC-COM

If you have a fail-safe lock, connect to NC-COM where LOCK ( + ) positive goes into NC (fail-safe) and LOCK ( – ) goes into COM.

Best practice: Always use an external access power controller when wiring up an ELECTROMAGNETIC lock (maglock). Do not use the Wet configuration!

WARNING – When connecting the lock in the WET configuration, ensure the negative of the lock goes into the COM port as shown in the diagrams below. Polarity matters.

Connect the Reader

The AC41 is rated to power readers at 12V up to 250mA via the + (VIN) and – (GND) connection. Verkada readers use the far left 4-port inputs while standard Wiegand readers use the middle 6-port inputs.

The Verkada AD31 uses the following color scheme:

+ - Red

– - Black

A - Purple

B - Blue

The Verkada AD32 and AD33 uses the following color scheme

+ - Red

– - Black

A - White

B - Green

Typical Wiegand wiring uses the following color scheme:

+ - Red

– - Black

D0 - Green

D1 - White

Note: Each door cassette can be connected to both a Wiegand reader and a Verkada reader. The AC41 supports simultaneous Verkada reader and Wiegand connections.

Connect the Inputs

Both the DPI (Door Position Indicator) and the REX (Request-to-Exit) inputs are dry contacts. Installing these inputs is optional. They can be configured in Verkada Command.

Door Position Indicator (Door Contact), optional

Note: Verkada AC41 expects the DPI to be NORMALLY CLOSED (NC)

Request-to-Exit (REX), optional

The REX can be configured to release the lock in Verkada Command (most commonly seen in electromagnetic locks) or simply show DFO (door forced open) events. The REX unlock time can also be configured.

Note: Verkada AC41 expects the REX to be NORMALLY OPEN (NO)

Powered Request-to-Exit (REX)

You may utilize the 12V port for the unused reader to power the REX device if necessary.

Wet configuration with emergency REX button release

Dry configuration with emergency REX button release

Insert the Cassette

To finalize the installation, insert the cassette back into the desired slot on the AC41. Then power the AC41 back on.


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