The Von Duprin PT790 is the OEM-specified 9-volt external power supply built for the Guard-X 2670 Series exit alarm. If you've installed a 2670 on a stairwell door or secondary exit and you need continuous, reliable power without depending on a battery replacement cycle, this plug-in transformer is the right accessory to order. It runs on 120VAC wall power and steps down to the 9-volt DC output the alarm requires, so you won't have to swap nine-volt batteries under normal operating conditions.

What makes this setup practical is how Von Duprin designed the backup logic. When the PT790 is connected, the 9-volt battery inside the 2670 alarm shifts to standby. It doesn't drain during normal operation. If the building loses power, the battery activates automatically and keeps the exit alarm live through the outage. That's a useful design for any facility where life-safety code compliance isn't optional.

Who Should Order the PT790

Facilities managers, security integrators, and door hardware contractors working with the Von Duprin 2670 Guard-X exit alarm will find that the PT790 is the only manufacturer-approved external power option for this device. It isn't a universal transformer. It's a purpose-built accessory for this specific product series, so verify your alarm's model number before adding it to your order.

If you need the alarm itself or want to build a complete door hardware specification, take a look at our full range of Von Duprin panic devices and accessories. We carry Von Duprin SL, IHR, XL, and XR series exit devices, along with electric strikes, power supplies, and trim options that work with the 2670 and related hardware.

Technical Specifications

Model: PT790

Brand: Von Duprin

Function: External plug-in power supply (transformer)

Input Voltage: 120VAC, 60Hz

Output Voltage: 9 Volt DC

Compatible Device: Von Duprin 2670 Guard-X Series Exit Alarm

Battery Behavior: When PT790 is connected, battery functions as backup only and does not discharge under normal operation

Mounting: Wall plug-in, no hardwiring required

Finish: US19 / 622, Powder-Coated Matte Black

How It Installs

No electrician required. The PT790 plugs directly into a standard 120VAC outlet near the door. The 9-volt output connects to the input terminal on the 2670 alarm housing, and from that point the alarm draws from wall power while keeping the battery in reserve for emergencies. No conduit, no junction box, no extra hardware. Most installations take a few minutes.

If your door sees heavy traffic or the installation needs to meet code requirements in a commercial or institutional setting, it's worth getting the correct Von Duprin panic device and this power supply specified together from the start. You can browse our full exit hardware catalog to find the right device for your door configuration.

Why Order from American Locksets

We stock commercial door hardware, access control components, and security-grade exit devices from Von Duprin, Schlage, Falcon, LCN, and other brands used in real commercial projects. When you order the PT790 here, you're buying from a distributor that handles Von Duprin products regularly, not a general marketplace reseller pulling from a third-party warehouse. If you need help confirming compatibility with your existing 2670 installation before placing an order, our team can assist.

Contractors and facilities teams ordering multiple components can cross-reference Von Duprin panic devices, electric strikes, and related exit hardware accessories in one place.