Morris Products Roller Ball Door Contact – Make & Break Circuit – 48 Contact Volts, 1.27 Hole Spacing – For Security, Alarm Systems & Opening, Closing Low Voltage Circuits, Switching Applications

UPDATE: Just wanted to confirm this switch is still working well. It was installed in an RV to turn on LED lights in an pantry. So no frequent use like in a home.----------I tested this switch as soon as I got it and it worked perfectly. Then a couple hours later after initial install I tested again and it didn't work. After a couple minutes of playing with it I realized that that metal contact plates under the screws go in only ONE way AND they have to be aligned properly to make the correct contact and complete the circuit. These small plates have a "tab" section - a portion of the plate that is wider - and can easily get out of alignment when trying to hold the wire and tighten the screw.I consider this a design flaw. Things that can only go in ONE way should NOT move around so easily. That's why lowered to 4 stars.BTW, if you are having trouble with which switch to get, read the description like this "Door Open-Circuit On" = Normally Closed or "Door Open-Circuit Off" = Normally Open.Oh and a 3/4 inch spade bit was a perfect fit. I actually wallowed out the hole a little to give a looser fit (easier to pull out) and allow for flush fit because the hole wasn't perfectly perpendicular with the door jamb.

Okay, first things first, because it seems like even in Q&A section there is no clear answer as to which version is which.- "Open Circuit On" is NC (Normally Closed)- "Open Circuit Off" is NO (Normally Open)I have no idea why they can't use this common nomenclature.Now, the real problem is their design for how the contacts engage/disengage. I think it is unnecessarily complicated. As a result of that, for the NC switch you have to push the ball almost all the way in for the circuit to break (open). This basically means that your door, window, or wherever you install this roller switch will have to rub against the front plate of this switch to make sure it pushes the ball all the way in and properly breaks the circuit. As opposed to simple button-style NC switches, where even light touch disengages the contacts and breaks the circuit. I'm attaching the simple schematics how typical NC switch operates, so that you can see how even slightest push of the button would disengage the contacts. So be aware that this switch is not it...

Great little low voltage door jam switch. I used it to turn on a closet light when the door is opened. If the light is 110VAC you will need a relay to switch the AC line voltage like Amprobe RC-120S Closet-Type Remcon Relay Switch available on Amazon. The relay is kind of pricy and it is supposed to be installed in a metal box to provide additional heat dissipation, although if you are using a low wattage LED closet light like I did at 15W or around 0.15A the relay is rated at 6.5A so it should never be stressed and you probably could get away without the metal box, but used one to be safe, since I wanted it to last 20 years without needing further attention. A little extra effort and cost up front is preferable to trouble later.

First, the unit arrived missing one screw...….quality control. Second, and others have pointed this out: the techno-jargon is inaccurate. This is for a normally-closed alarm circuit......I wanted to activate a buzzer when the door was opened. Should read, "Open the door, circuit off." Not impressed with seller.

If installed properly, it works perfectly. Make sure the gap between door and the door-jam is very small, 1/8". If the gap at the prefered location is too large, you can always glue a shim to the door to reduce the size of the gap. Another reviewer had already noted this, so was not an issue for my installation . Also, make sure the wire is placed between the lock washer and the base washer. If it is placed under the base washer, the mechanical operation of the switch will be impaired.

Bought this normally closed switch to turn light on when door opened. The first one I ordered worked intermittently and then not at all. Returned for replacment. Second switch results: when door closed light was off - when door opened, light came on then right back off. Reason: as ball extended out it passed thru its normal state of on (where it should have remained) but when ball fully popped out, the circuit opened again and the light went back off. Returned for full refund.

After approximately two months in use the switch is intermittent, apparently the contacts are dirty, spinning the ball several times seems to clean them. I have to do this repeatedly, as the lights get dim if the contacts are dirty. I'm using this in a door frame to control 12v exterior step lights.

Do not use on line voltage. This is a low voltage switch only. My application is 12 volts for a door alarm. Line voltage requires a junction box, low voltage does not. Install low on the door so fishing the wire is easier or you will need to remove and reinstall the door trim.

Really cheap & flimsy. It flicked and shorted out with the first use.