I have never installed a DPS.
Have allways used the built in status in either maglock's or strike's. Much better way to see that a door is shut and locked. Maglocks offer "bond" or "sense" status that tells you that the magnet is engaged. Strikes offer latch bolt monitoring and latch bolt strike or keeper status which when used in series give you positive shut and locked (secure) feedback.
We have used the GRI 18412's for our recessed door contacts, and they also make a good surface mount option. They aren't terribly expensive either.
GRI Door Contacts
In new installs where we were doing access AND intrusion, I used to use the GRI AA/AC dual contacts, so we didn't have to install two separte ones. Otherwise I used their standard recessed and surface mounts.
They seemed to be more reliable, rust and fail less often, and had rare earth magnets for wide gaps. They also had the handy plastic mounting legs for steel doors with a top channel, which I don't recall being too common among manufacturers.
I tried to change out to other manufacturers occasionally, but techs always preferred GRI and complained about others.
Silva Consultants | 02/06/15 05:36pm
Sentrol used to be the dominant market leader in magnetic contact switches. I have probably specified tens of thousands of Sentrol switches over the years. They were then bought by GE Security and went downhill fast, and then spun off to Interlogix. They still make a good product, but the number of product options available is only a fraction of what Sentrol originally had.
GRI is now my preferred manufacturer of magnetic contact switches. Honeywell Security also offers some good options.
It is my opinion that bonding sensors in mag locks and latch bolt monitors in electric strikes should be used in conjunction with, not in place of, door position switches. They provide different functions and you can get some interesting results when you try and substitute one for the other.
For example, many access control systems reset the door unlock time when a door is opened. This is to prevent a second person from passing through the door after the first person walks through. If you use a bonding sensor on a mag lock as your door switch input, the door has the potential to immediately relock itself after a card has been presented.
IPVMU Certified | 02/06/15 05:54pm
We've had issues with maglocks with built in DSM (door status monitoring), though not through any fault of the maglock. Our technicians have had a hard time lining up the maglock properly and as a result we have seen several doors with intermittant false "door held" or "door forced" alarms. The RCI mini-mags that we have used most often are not very forgiving in lining up the DSM contact.
IPVMU Certified | 02/06/15 09:21pm
Thanks to everyone who has replied. Your information is helpful. I am specifically looking for a good "monitored" electric strike lock for use in exterior doors. Our standard is to use door prop alarms. When the sensing devise built into the electric strike is not consistently accurate, we get door prorp alarms on doors that are actually adaquately locked. We welcome the alarms when the door is not secure, but alarms on secured doors is a real problem.
We have always opted for optical sensors as opposed ot the mechanical plunger type. We fear dirt and the elements will impact the movment of the plundger. If anyone is aware of a good/reliable monitored electric strike, I would love to hear about it.