By Kent · Lock Depot Staff Writer

Third-floor stairwell door, a Von Duprin rim panic bar already on it, and the property manager wants badge access for the new tenant. The door is fire rated. That one fact throws out half of what people try. You do not touch the bar's egress side and you do not grind on a rated frame. You electrify the strike the rim device latches into, and that strike is the Von Duprin 6111-DS-24VDC-US32D.

Electric strike for a fire-rated door with a panic bar

The 6111 is the strike Von Duprin built for rim exit device openings. Single door, or one leaf of a pair running a mullion. Heavy-duty stainless steel body, 3/4" latchbolt throw, 6" faceplate, 24VDC. It carries a UL 10C fire rating to 3 hours on single doors, the listing that lets it live on a rated opening at all.

The word that matters is rim. A rim device throws a latch out the back of the case into a strike on the frame, and that latch is what the 6111 catches. It works with Von Duprin 22, 33A, 35A, 88, and 98/99, and with Falcon, Precision, Sargent, and Yale rim devices, so a mixed building does not force you to rip out working hardware. It does nothing for a vertical rod or mortise device. I had a crew order two for a concealed vertical rod opening and call back angry a week later. Look at the back of the device first. If the device itself is still open, start with Von Duprin 98/99 on a hollow metal fire door.

The panic bar is not the access control. The strike is.

This is the part I will not bend on. Free egress from the inside is absolute. Somebody pushes that bar in a fire, in an outage, with an expired badge, at 3am with the panel dead, and the door opens. Access control does not get a vote.

So you leave the bar alone and control the outside. The 6111 releases the rim latch on a valid credential and the door pulls open from the corridor. Push from the stairwell side and you are out regardless, because that motion is mechanical and the strike is not in its path.

The related trap is dogging. A fire-rated device does not get held down for daytime traffic the way a normal one does. If the building wants that door free during business hours, that is a latch retraction job with a fire alarm tie-in, not this strike.

Swapping an old Von Duprin 3031

Here is why integrators and locksmiths land on this exact model. The 6111 is a drop-in replacement for the old Von Duprin 3031. Same cutout, no frame modification needed.

Understand what that saves on an occupied building. A rated frame is a listed assembly. Cut it for a strike that does not fit the existing prep and you are grinding on a fire-rated frame, patching it, and explaining that patch to whoever inspects the building. In a leased tower that is a permit conversation. Dropping a 6111 into an existing 3031 pocket is an hour with a screwdriver and the wire already in the frame. If you maintain a building from the 80s or 90s with 3031s failing one at a time, this is a one-for-one replacement plan, not a frame job. Pull the old strike and check the pocket first; an opening somebody already hacked may not have original prep.

Fail-safe or fail-secure on a rated opening

Fail-safe unlocks when power is lost, so the door opens freely during an outage. Fail-secure stays locked, with key override always available. On an ordinary door that choice is a security preference. On a fire-rated door it is not.

A rated opening has to stay positively latched to work as a barrier. A strike that gives up its latch when the building loses power leaves that door free to swing during the exact event the rating exists for. That is why the 6111 ships factory configured fail secure, and why fail secure is the right answer on most rated openings. You lose nothing on life safety, because the bar covers egress mechanically.

A fail-safe application on this opening has to be specified up front, and it is worth a word with your authority having jurisdiction first. Call 877-365-5625 and tell us what the door does. Do not guess at a conversion in the field.

What the dual signal door position switch actually buys you

The 6111 comes with a dual signal door position switch built in. One line on a spec sheet. In a building with a propped-door problem it is the reason to pick this strike. The head end knows the state of the opening without anyone drilling a separate contact into a rated frame, and it can tell a closed door from one sitting open with a wedge under it.

Stairwell doors get propped. Smokers prop them, movers prop them, the cleaning crew props one at 9pm. Without monitoring you find out at the next walkthrough, or never. With the strike reporting position, the panel throws a held-open alarm in whatever window you set and somebody walks up there in five minutes.

Finishes we stock

The faceplate shows on the frame. Same strike underneath.

• 6111-DS-24VDC-US32D, US32D satin stainless. The default on commercial and institutional work.
• 6111-DS-24VDC-US32, US32 bright stainless, for polished hardware.
• 6111-DS-24VDC-US10B, US10B dark bronze, for lobby and tenant entries.
• 6111-DS-24VDC-US4, US4 satin brass, for older buildings running brass trim.

Common questions

Can I add a card reader to a fire-rated door with a panic bar?

Yes, by electrifying the strike instead of the exit device's egress function. The rim device keeps working mechanically from the inside while the 6111 releases the latch from the outside on a valid credential. Free egress stays intact.

Will the Von Duprin 6111 replace my old 3031 strike?

Yes. It is a drop-in replacement for the 3031 and uses the same cutout, so no frame modification is needed. Pull the old strike, confirm the pocket is original, and set the new one in.

Should the 6111 be fail-safe or fail-secure on a fire door?

Fail secure on most rated openings, and that is how the 6111 ships from the factory. A rated door has to stay latched to work as a barrier, and the bar already covers egress. A fail-safe application has to be specified up front, so call 877-365-5625 rather than converting one in the field.

Does it work with a non-Von Duprin exit device?

Yes, with rim devices from Falcon, Precision, Sargent, and Yale, along with Von Duprin 22, 33A, 35A, 88, and 98/99. It does not work with vertical rod or mortise devices of any brand, because there is no rim latch to catch.

Lock Depot stocks the 6111 in all four finishes, 24VDC, with the dual signal door position switch. Browse the rest of the line on the Von Duprin hub, or read Von Duprin 98/99 on a hollow metal fire door if the device is still open. Call 877-365-5625 with the exit device series, whether there is an existing 3031 cutout, and single or pair, and we will confirm the right version before it ships.