What can I say? I supposed I've been blinded by datasheets. (I went straight to Edit & didn't find a Delete there & never looked back at the original post until now. Thx.)Isn't there a Delete button at the bottom of the post?
What can I say? I supposed I've been blinded by datasheets. (I went straight to Edit & didn't find a Delete there & never looked back at the original post until now. Thx.)Isn't there a Delete button at the bottom of the post?
Success! ...with a little modification -- I had to add a 10k in series with the alarm sensor and Drain. Works perfectly.The MOSFET gate looks like a capacitor and has no significant current flow, so its drain-source current is completely separate from any current flowing in the gate control circuit.
The only thing in common between the two sides of the circuit is the common (ground) and there is no current flow in the common between the two sides.
If you are confused about current, just follow the current loop. Current can only flow in a loop so if there is no loop there is no current flow.
In this case there is a loop on the MOSFET output and a loop at the MOSFET input, but no loop between the input and output.
Well that makes little sense to me, but if it works, great.to try inserting a resistor in series with the alarm sensor and voila!
I agree -- that wireless sensor circuit is a strange beast. It seems to be sensitive to the resistance delta between open and closed states as opposed to the actual values. I suppose it's got a comparator inside instead of just simple logic gates. Would love to see the schematic someday...Well that makes little sense to me, but if it works, great.
That does seem strange. Maybe you don't need the mosfet, what would happen if you just install a 10K resistor in series with the switches and the alarm sensor ?Success! ...with a little modification -- I had to add a 10k in series with the alarm sensor and Drain. Works perfectly
OMG. (And I never say that!) That works! Even tho that's what I was essentially doing when I added the resistor in series with the MOSFET, it's the exact opposite of what I would have expected.EDIT: Lets see here. The 6 ohms of resistance from the switches would not work but the relay circuit did.
That does seem strange. Maybe you don't need the mosfet, what would happen if you just install a 10K resistor in series with the switches and the alarm sensor ?
SG.
Not at the moment. Do you have any info on the wireless module, brand, model number, etc?What the hell is going on here? Any ideas?
I'm sorry, but an NDA prevents me from identifying the hardware.Not at the moment. Do you have any info on the wireless module, brand, model number, etc?
SG
Did you try different values of resistors?zone 2 wouldn't work with just the added series resistor
Yes, and since I'm flying blind, I went up & down the scale. Nothing worked on this zone except the MOSFET switcher. So I've resigned myself to the fact that I'll need to use that for each zone. A fringe benefit of the switcher/driver circuit is it lets me add an LED on each zone for visual status of all the doors and windows, by zone. But I'll still lie awake for a more nights trying to figure out what the heck is going on with these wireless sensors and their very strange behavior.Did you try different values of resistors?
SG
Excellent.A fringe benefit of the switcher/driver circuit is it lets me add an LED on each zone for visual status of all the doors and windows, by zone.
Despite all of the strange observations, this sounds to me like a normally closed Class B intrusion alarm with a normal window of operation, Either the protected loop circuit heading to ground or heading to battery voltage would cause an alarm. Only one value for the EOLR (end of line resistor would be valid. I have a 'concept' diagram if you are interested.Yes, and since I'm flying blind, I went up & down the scale. Nothing worked on this zone except the MOSFET switcher. So I've resigned myself to the fact that I'll need to use that for each zone. A fringe benefit of the switcher/driver circuit is it lets me add an LED on each zone for visual status of all the doors and windows, by zone. But I'll still lie awake for a more nights trying to figure out what the heck is going on with these wireless sensors and their very strange behavior.
I thought you are trying to hack a wireless alarm system. Does this alarm have provisions for normally wired sensors?this sounds to me like a normally closed Class B intrusion alarm
Usually there is an "edit" option that allows erasing stuff and then saving the change. I have used it and it works.Isn't there a Delete button at the bottom of the post?
by Aaron Carman
by Jake Hertz
by Jake Hertz