electric latches

[hgupta1]

I would use a DPDT relay to remove both the pos and neg of the maglock as well as add the approprate suppressors in parallel, if they're not included with the maglock to isolate the maglock from the panel itself because of the inrush current a maglock takes, combined with being powered off a dedicated separate supply.

I didn't realize that was a problem, and I definitely don't want to burn out my Elk M1G (I am using output 3 on it right now).

Can you recommend a good DPDT relay? I am new to this and haven't really used relays or maglocks before. Also what it are "appropriate supppressors?"

I was thinking about getting an ELK M1-XOVR to add some more maglocks around the house. Would that solve the inrush current problem?

Thanks!

-hg

 

[hgupta1]

Today was the first rea;l test of my electronic doggie gate... it was locked all day while people were working in my basement. When they left, I turned off output 3 remotely, and watched my basement camera waiting for the doggie gate to spring open. It never did! It remained closed. I think it is residual magnetism, but it was strong enough to the gate despite the hinge springs that keep the gate in the open normally.

I'm not sure what I did wrong or how to fix this, except to use another hinge spring. Any ideas on how to fix it?

 

[BraveSirRobbin]

I would be very surprised if it is residual magnetic force. I leave a substantially larger magnetic gate on an exterior gate all day and don't have this problem. My magnetic holder is not ridigidly mounted to the gate and can float a bit so it retracts ever so slightly when the magnet is off. Can you possibly adjust yours to achieve this same effect?

Also, are you sure your power is removed from the magnet? Can you test this with a piece of metal?

 

[hgupta1]

Thanks for the reply.

I doublechecked, and power is being removed. In fact, it was swung open at the slightest touch. So I increased the tension on the spring hinge, and tried again.

If the maglock is energized for a few minutes, there is no problem, and the gate swings open immediately after power is disengaged. But if it is energized for a few hours, it sticks. That's what makes me think that it is residual magnetism built up over a few hours (unless output 3 isn't completely opening the circuit). I did also order an ELK-M1RB, so maybe that will be better at disengaging the current if that is the problem. Of course, it may be my cheap ebay purchased maglock. The name brand ones aftertise "no residual magetism".

It stuck again today after I left it for 3 hours. D'oh!

 

[Del91574]

Maglocks need supressors to be installed in parallel with the power to help counteract the magnetic flux and inrush currents/collapse of the magnetic fields and spikes.

Northern Computer (Honeywell) has one listed under P/N S4, which is similar to other manufacturer's units I've installed. Other manufacturers either build them in or include them with the access package. That sounds like the first step to help with your cheapie strike.

 

[tmbrown97]

or maybe just a little spring to give it a nudge? These come to mind - from the custom car guys who shave their door handles and need a way to pop the door:
http://www.slickcar.com/productdetails.asp?ProductID=494