Electronic Challenge Help Requested

I had a Macintosh rack mount early style solid state stereo amplifier that used incandescent lamps in the bias circuit for stability. You had to tighten the lamps now and then..

Jamie

Update Info:

I was on site today and did some testing. When the motion output is connected to the bulbs and the motion is stable and when power is applied(for Winston) the current is .01 amps or 10 milliamps. For what it is worth when the motion is tripped the current draw is 1.6 amps.

I have on the way to me at this time a number of 20k ohm 2 watt resistors for some experiments. Hopefully this will be the ultimate fix for this project.

I do have an alternative solution to make this work. That would be to connect one of the bulbs and the sense wire of the module to the motion output and the other bulb to the output of the module. What happens is that when the motion is activated it turns on the one bulb and since this output is connected to sense wire of the module it then turns on the other bulb when the module is activated. The only downside of this setup is that when the module is trigger from the alarm panel it only turns on one bulb. Not really the desired function but I have tested this and it does work.

I would like to thank all that have helped me brain storm this challenge. Please give yourselves a pat on the back along with a few attaboys!!

Ya'll have a good rest of the week.

Les

you can get yourself a handful of 1W, 15000

to the bulbs and the motion is stable and

Ouch. That's a lot.

That's 720 mW per resistor with the light on. The '2 W' rating is for free air, so please don't box the resistor tightly. :) Consider the heatsink - compatible resistors so you can get rid of heat.

some experiments. Hopefully this will be

George Simon just mentioned that you're still gonna end up with 75 V if you pull down that leakage current with a 20K resistor. Is that far enough below the threshold voltage of the sense line on your module? I Dunno (TM).

We know the threshold voltage is above 0.095 V because that is what your first bulb leaves you when you connect it as you mention below.

There is a whole bunch of uncertainty between 75 V and 0.095 V! :)

You now have a purpose for that nifty Variac autotransformer you've been hiding. Connect it to the sense line and determine just what that threshold voltage is, for each one of your modules, I advise.

Work Safely (Other TM)

one of the bulbs and the sense wire of the

What happens is that when the motion is

wire of the module it then turns on the

that when the module is trigger from the

have tested this and it does work.

Please give yourselves a pat on the back along

Back 'atcha, Les.

--Winston

--
Is that the current into the motion detector from the mains or the
current into the lamps?

John,

That was the current draw of the lamps when OFF(.01amps) and then when ON(1.6amps).

I don't have a powerstat of any kind to test the trip point of the sense wire. But, I am thinking that really should not matter much.

At this point I am still waiting for the resistors to come in. Then I can play (safely) or have some controlled diagnostic evaluations with out any serious catastrophic failures.

Thanks,

Les

(...)

ON(1.6amps).

But, I am thinking that really should not

It'll matter if you need to provide step - down transformers on the 'slave' outputs of your PIR sensor lights in order to drive your Insteon modules properly. :)

I bet the engineers at Smarthome know the threshold voltage of the sense input on Item# 2475S2 by heart and can get you a good answer very quickly:

(safely) or have some controlled

--Winston

--
OK, but where did you measure the current?

Between the mains and the motion detector or between the lamp sockets
and the lamps?

Between the output of the motion and the lamp(socket).

The red wire off the motion detector that I am having the initial problem with having the leakage voltage and the lamp socket - lamp - neutral(load)

Les

BUT, I do not need to know. Not necessary. Not re-inventing the wheel. Just making it turn to my desires.

Les

On Thu, 22 Mar 2012 20:19:39 -0400, "ABLE1" wrote:

--- Les,

This should work for you: (View using a fixed-pitch font)

. MOTION DET . +------------+ . | R1 | C1 R2 . | +-[12k]-+-|-[330nF]-[100]-+--------+ . | | | | |K |A .120AC>-|--+-O | | [1N4002] [1N4002] . | | | | |D1 D2| . | | ACOUT . | | | | | | . +----------|-+ | +----+ |NO NC . | | |+ | O-> |------------------------------+--------+-----------+

R1 is the OFF resistance of whatever's doing the switching in the motion detector, C1 is a lossless reactance which, in series with R2 and the resistance of the relay coil, will provide the impedance necessary to limit the current in the coil to 6.25mA when the motion detector is hot.

R2 is used to limit the current into the diodes to a safe value if the motion detector goes hot on either the negative or positive peak of the mains.

The relay is an OMRON G5V-1 24VDC:

which has a 24VDC coil with a resistance of 3840 ohms and is driven by half-wave rectified AC smoothed by C2

R3 is used to provide a relatively low-impedance path to ground for the leakage current from the motion detector and makes sure that the voltage into C1 won't be high enough to fire the relay.

When the motion detector goes hot the mains voltage will be impressed across R3 for a few milliseconds (until the relay disengages from the NC terminal, so during that time the resistor will be dissipating quite a bit of power.

Assuming that the input to the resistor was a rectangular waveform 170 volts high and 5 milliseconds wide would make the power dissipated by the resistor about 29 watts, but for 5 milliseconds that comes out to

145 millijoules.

A likely candidate for that resistor would be a 1/2 watt Panasonic ERG(X)S:

which can take a 50 watt hit for 50ms.

I actually built the circuit and tested it with a 1/4 watt carbon film, and although it worked OK, I think that's a little too close for comfort.

Here's a sim just for fun:

Version 4 SHEET 1 1332 744 WIRE -192 -80 -384 -80 WIRE 128 -80 -144 -80 WIRE 672 -80 176 -80 WIRE 1056 -80 720 -80 WIRE -16 -16 -80 -16 WIRE 96 -16 64 -16 WIRE 208 -16 96 -16 WIRE 240 -16 208 -16 WIRE 416 -16 384 -16 WIRE 528 -16 416 -16 WIRE 416 16 416 -16 WIRE 528 16 528 -16 WIRE -80 112 -80 -16 WIRE -80 112 -288 112 WIRE 0 112 -80 112 WIRE 96 112 96 -16 WIRE 96 112 80 112 WIRE 208 112 208 -16 WIRE 768 112 208 112 WIRE 928 112 768 112 WIRE 1104 112 1008 112 WIRE 768 128 768 112 WIRE -288 160 -288 112 WIRE 16 208 16 160 WIRE 528 240 528 80 WIRE 608 240 528 240 WIRE 944 240 944 160 WIRE 944 240 608 240 WIRE 768 304 768 208 WIRE -288 320 -288 240 WIRE 528 320 528 240 WIRE 608 320 608 240 WIRE 832 320 816 320 WIRE 944 320 944 240 WIRE 944 320 896 320 WIRE -288 448 -288 400 WIRE 16 448 16 288 WIRE 16 448 -288 448 WIRE 64 448 64 160 WIRE 64 448 16 448 WIRE 416 448 416 80 WIRE 416 448 64 448 WIRE 528 448 528 400 WIRE 528 448 416 448 WIRE 608 448 608 384 WIRE 608 448 528 448 WIRE 768 448 768 384 WIRE 768 448 608 448 WIRE 816 448 816 368 WIRE 816 448 768 448 WIRE 992 448 992 160 WIRE 992 448 816 448 WIRE -384 480 -384 -80 WIRE -192 480 -192 -80 WIRE -192 480 -384 480 WIRE -144 480 -144 -80 WIRE 128 480 128 -80 WIRE 128 480 -144 480 WIRE 176 480 176 -80 WIRE 672 480 672 -80 WIRE 672 480 176 480 WIRE 720 480 720 -80 WIRE 1056 480 1056 -80 WIRE 1056 480 720 480 WIRE -288 560 -288 448 FLAG -288 560 0 SYMBOL voltage -288 144 R0 WINDOW 3 24 96 Invisible 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 WINDOW 0 12 103 Left 2 SYMATTR Value SINE(0 170 60) SYMATTR InstName V1 SYMBOL res 80 -32 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R4 SYMATTR Value 12k SYMBOL sw 96 112 M270 WINDOW 0 -29 -29 VRight 2 WINDOW 3 -59 -33 VRight 2 SYMATTR InstName S1 SYMBOL voltage 16 192 R0 WINDOW 0 -44 102 Left 2 WINDOW 3 -242 110 Invisible 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V3 SYMATTR Value PULSE(0 24 .0417 1u 0 1) SYMBOL sw 768 400 R180 WINDOW 0 39 5 Right 2 WINDOW 3 44 -22 Right 2 SYMATTR InstName S2 SYMBOL res 752 112 R0 SYMATTR InstName R3 SYMATTR Value 1000 SYMBOL Digital\\inv 896 384 R180 WINDOW 3 8 104 Invisible 2 SYMATTR Value trise 1u tfall 1u vhigh 24 SYMATTR InstName A1 SYMBOL res 544 304 M0 SYMATTR InstName R1 SYMATTR Value 3840 SYMBOL cap 304 -32 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C2 SYMATTR Value 330n SYMBOL diode 544 16 M0 WINDOW 0 -37 38 Left 2 WINDOW 3 -52 68 Left 2 SYMATTR InstName D5 SYMATTR Value ES1D SYMBOL cap 592 320 R0 SYMATTR InstName C3 SYMATTR Value 10µ SYMBOL diode 400 80 M180 WINDOW 0 38 31 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D6 SYMATTR Value ES1D SYMBOL sw 1024 112 M270 WINDOW 0 -19 -21 VRight 2 WINDOW 3 -49 -25 VRight 2 SYMATTR InstName S3 SYMBOL res 400 -32 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R2 SYMATTR Value 100 SYMBOL voltage -288 304 R0 WINDOW 3 24 96 Invisible 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 WINDOW 0 12 103 Left 2 SYMATTR Value PULSE(0 1500 .104155 1u 1u 10u) SYMATTR InstName V2 TEXT -272 504 Left 2 !.model SW SW(Ron=.01 Roff=1G Vt=12 Vh=0) TEXT -272 536 Left 2 !.tran 0 1 0 10u TEXT 1096 112 Left 2 ;>

TEXT 1120 112 Left 2 ;OUT TEXT -128 -112 Left 2 ;MOTION DETECTOR TEXT 328 -112 Left 2 ;RECTIFIER - FILTER TEXT 840 -112 Left 2 ;SPDT RELAY TEXT -320 -112 Left 2 ;MAINS

-- JF

--
Oops...

I inadvertently used a 24VDC Omron GS5-1, thinking it was a G5V-1, so
the coil drive may be too high...

John,

Thanks for all the input. Very interesting. Today I was on site again and did some testing.

I had with me the 20k 2 watt resistors. What I found was that with one resistor from the motion detector output to Neutral it pulled leakage voltage down to 16.5vac. When the sense wire from the module was connected the module was triggered and the lights turned ON.

Applied 2 resistors in parallel and the voltage dropped to about

8vac and again when the sense wire was connected the module was triggered and the lights turned ON.

Applied 3 resistors in parallel and the voltage dropped to about

5.5vac and again when the sense wire was connected the module was triggered and the lights turned ON.

Applied 4 resistors in parallel and the voltage dropped to about

4.2vac and it was at this point the module did not trigger. So it would seem that the threshold voltage of the sense wire is approximately 5vac.

By my crude testing I am thinking a 3.9k 2 watt resistor should do the trick.

Any thoughts??

Thanks,

Les

(...)

some testing.

resistor from the motion detector output to

So 0.825 mA of leakage current, not 10 mA.

again when the sense wire was connected the

again when the sense wire was connected the

was at this point the module did not

approximately 5vac.

Ouch. That's pretty low.

3.7 W into a 2 W resistor is a non-starter. :)

This is the Pulse Engineering 020-5371.0 (Digikey BV020-5371.0-ND). It is a 120 to 13.5 V transformer that will give you about 2.5 VAC when off and 13.5 VAC when on, to drive your module from the output of your PIR light.

It measures 23 mm x 22 mm x 19 mm. One part. Very little wasted power.

--Winston

a=20

into=20

relay=20

I'm just catching up on your post and it seems that there may be no good =

reason to use the sense lead at all, in which case it may be = deactivated. I=20 think its only purpose is to require the motion detector AND the = automation=20 device to be turned ON in order to light the lamps. In other words, a = wired=20 AND gate.

If you want to be able to turn on the lamps EITHER because motion is=20 detected OR there is an alarm condition which triggers the automation=20 device, you want a wired OR gate. So you should be able to connect the=20 switched output lead of the automation device to the red lead of the = motion=20 detector which is also connected to the lamps. So the lights will turn = ON=20 anytime motion is detected OR there is an alarm.

That seems almost too simple. Maybe I'm missing something?

Good luck,

Paul

(...)

reason to use the sense lead at all, in which

detector AND the automation device to be

OR there is an alarm condition which

able to connect the switched output lead of

connected to the lamps. So the lights will

I believe that is the case Paul, though I agree with your larger idea. :)

From the readings supplied by the OP Les, (ABLE1) it is pretty clear that the red wire from his PIR security light isn't connected to the lamps in the same housing.

With the PIR sensor inactive, Les indicated that the red wire measured 120 VAC WRT neutral, which is a somewhat larger value than you would expect to see across the filaments of two extinguished flood lights.

--Winston

reason to use the sense lead at all, in which

detector AND the automation device to be

OR there is an alarm condition which

able to connect the switched output lead of

connected to the lamps. So the lights will

--
Not necessarily, since with the lamps in place, and off, the leakage
resistance of the switch would be connected to neutral through the low
off resistance of the lamp.

From Les's last post it appears that the leakage resistance of the
switch in the motion detector is about 130 - 140 kohms:

  

            E2
            /
  E1  | -+-O    |
    |      |
    +-[R1]-+
           |
          [R2]
           |
AC>--------+

With E1 being the mains voltage, R1 being the leakage resistance, and
R2 being the resistance of his test resistors, R1 will be:

           R2 (E1-E2)
     R1 = -----------
               E2

which comes out to:

  R2    R1
-----+------ 
 20k   130k
 10k   140k
  5k   138k

Substituting two 100 watt lamps in parallel for R2, then, yields a
cold resistance of about 8 ohms and a voltage at E2 of about 7
millivolts.

However, with R2 open the voltage at E2 will measure close to 120V
because of the high impedance of the voltmeter.

So, because of Les's posts, I believe the red wire is connected to
lamp hot.

Easy enough to find out, just continuity test.  With the mains
disconnected...

(...)

Right you are, John.

I hadn't remembered that Les mentioned on March 17: "When bulbs are installed and the unit is powered up the output to the bulbs is at zero(0). If the bulbs are not connected or installed the output is 120vac."

So, Les. What about John's idea? If the switching device in your security system module is 'high side' as is he switching device in your PIR floodlamp, what is stopping you from placing them in parallel so that either or both can power the lights?

Would the security module be confused by having it's sense wire connected to it's own output?

--Winston

All,

It would seem that I could not see the forest for the trees. I was concentrating so hard on the way the mfg. was showing how to wire this thing up and proceeded that way. When Paul posed his question of why not just connect both outputs to the lamps I wanted to use a hammer on my head. Then I stopped myself before doing some mass destruction and thought that maybe the mfg. had a reason for not describing this way to make the connections in that it may back-feed the module and cause it to blow up or something. Just contacted tech support and was told that it will NOT cause a problem in this wiring plan. Just cap the yellow sense wire and go for it. My next small concern would be that of back-feeding the motion output may cause a similar issue, but I doubt it would.

So what this comes down to, is that for once I decided to RTFM and to follow the instructions and should NOT have done so.

Thanks all for the help in this challenge. And a special thanks to John for stepping back and turning on the light. :-)

Regards,

Les

--
Be very careful here.

While the switch in the module may be able to hold off the 120V from
the motion detector, and vice versa, make sure that their outputs are
in phase or you'll be in for a nasty surprise if they're not and they
both go hot.