babadono Posted March 6, 2014 Share Posted March 6, 2014 Bruce, Are you saying K1 is definitely a reed or IF it is a reed relay you will not hear it? I hate reed relays! I have replaced 100s if not 1000s in automatic test equipment. They have no mechanical force to put them in their "normal" position when the coil is de-energized. Eric Quote Link to comment Share on other sites More sharing options...
Mallette Posted March 6, 2014 Author Share Posted March 6, 2014 Seem to be quite a few such 24v relays available. Is the timing part of the relay, or another circuit? Guess I can worry about that if I can determine whether it is the issue or not, but since at work figured I could at least get an idea of what I might be looking for later. Dave Quote Link to comment Share on other sites More sharing options...
babadono Posted March 6, 2014 Share Posted March 6, 2014 (edited) Dave, The timing is another part of the circuit, Q1 and Q6 and associated components on page 9. But let's not get ahead of ourselves. Do the checks in post 20. Eric Edited March 6, 2014 by babadono Quote Link to comment Share on other sites More sharing options...
Marvel Posted March 6, 2014 Share Posted March 6, 2014 Are you saying K1 is definitely a reed The parts list in the pdf says it IS a reed relay.Bruce Quote Link to comment Share on other sites More sharing options...
babadono Posted March 6, 2014 Share Posted March 6, 2014 Bruce, Ok I see it now in the parts list. Sorry. It IS a reed relay. Sucks. Eric Quote Link to comment Share on other sites More sharing options...
Mallette Posted March 6, 2014 Author Share Posted March 6, 2014 Okies, have the board in my hand. Very nice construction! Even a novice like me could locate the correct board and pull it out. I fear any testing in situ under power may be problematic as it's at the base of the board and close to another. Will check to see if it is open. Frankly, I hope so as perhaps finding a replacement won't be that hard and I can handle the r&r. Didn't fully respect this thing until the other day when she SANG! Perhaps it's payback... Dave Quote Link to comment Share on other sites More sharing options...
Mallette Posted March 6, 2014 Author Share Posted March 6, 2014 No combination of these pins reads anything other than zero, doctors. Dave Quote Link to comment Share on other sites More sharing options...
djk Posted March 7, 2014 Share Posted March 7, 2014 (edited) The relay coil is from pin 5 to pin 8 (page 15), the drive circuit is on page 8. Page 6 shows none of the outlets are fused. If the coil is open, you need a new relay. You may have a hard time finding the proper reed-relay type (normally closed DPST). If that's the case, buy a gold-crosspoint nitrogen-filled Omron from Digi-Key and run wires to make it work. http://www.digikey.com/product-detail/en/G5V-2-H1%20DC24/Z110-ND/277846 Edited March 7, 2014 by djk Quote Link to comment Share on other sites More sharing options...
Mallette Posted March 7, 2014 Author Share Posted March 7, 2014 (edited) Thanks. Done for the evening due to other responsibilities and dark thirty oilfield work schedule. Just to be clear, 0=Open? Dave Edited March 7, 2014 by Mallette Quote Link to comment Share on other sites More sharing options...
djk Posted March 7, 2014 Share Posted March 7, 2014 Depends on your meter, 0L may show up, or something similar. If the coil is OK it will show some lower resistance, 1000Ω~2000Ω or so. Quote Link to comment Share on other sites More sharing options...
Marvel Posted March 7, 2014 Share Posted March 7, 2014 That would certainly hold up a lot better. We used some older Omron relay and they would be opening/closing continuously and held up really well on the industrial knitting machines where we used them. Bruce Quote Link to comment Share on other sites More sharing options...
babadono Posted March 7, 2014 Share Posted March 7, 2014 (edited) No combination of these pins reads anything other than zero, doctors. Dave Huh, what pins? zero ohms? or volts? Dave, You have the output amplifier completely removed from the unit? If so you should read close to zero ohms from J1 pin 6 to pin 7 and J1 pin 6 to J2 pin 1. This will test that the NC contacts of the relay are in fact closed. Also as DJK stated you should read 1 to 2 K(or possibly greater but not open) OHMS not volts across the relay coil, probably easiest to measure this across diode CR4. How fancy is your meter? Does it have seperate Ohms and Diode settings. These preliminary measurements should be done in the Ohms position as oposed to Diode so your meter does not forward bias any of the semiconductor junctions. BTW do you have any Deoxit? As long as your taking things apart might as well clean'em up as you put it back together. Well I guess we won't hear any more from you tonight. Catch ya tomorrow. Eric Edited March 7, 2014 by babadono Quote Link to comment Share on other sites More sharing options...
Mallette Posted March 7, 2014 Author Share Posted March 7, 2014 (edited) I'll have to check again tonight. Seriously confused... If so you should read close to zero ohms from J1 pin 6 to pin 7 and J1 pin 6 to J2 pin 1. This will test that the NC contacts of the relay are in fact closed. Good or failed, wouldn't this be the case since NC is the default? And if it were stuck open wouldn't I be hearing sound? Intuition would suggest since the de-energized state, according to the diagram, is NC this would read no resistance. It is hard for me to understand how I can test it without powering on and off to see if it shows a an open circuit when energized, a closed circuit when off. Sorry for the slowness of the pupil here... Dave Edited March 7, 2014 by Mallette Quote Link to comment Share on other sites More sharing options...
babadono Posted March 7, 2014 Share Posted March 7, 2014 I'll have to check again tonight. Seriously confused... If so you should read close to zero ohms from J1 pin 6 to pin 7 and J1 pin 6 to J2 pin 1. This will test that the NC contacts of the relay are in fact closed. Good or failed, wouldn't this be the case since NC is the default? Yes, unless there are bad solder joints or foil traces on the board that have opened up(burnt). And if it were stuck open wouldn't I be hearing sound?Yes, that is why i don't think this is the problem Intuition would suggest since the de-energized state, according to the diagram, is NC this would read no resistance. It is hard for me to understand how I can test it without powering on and off to see if it shows a an open circuit when energized, a closed circuit when off. Correct you can not completely test it with no power and with it dis connected from the driver circuitry that is generating the power on time delay. But since you completely removed the board I was just trying to suggest what you could test with it removed. This is DualPoleSingleT-Normally Closed reed relay. One pole for each channel. Single throw means it is either on or off and Normally Closed means in its un energized state the switch is closed allowing current to flow hence it should read close to 0 ohms Sorry for the slowness of the pupil here... No need to apologize, at least not to me. I have been an electronic tech/test engineer for 30+ years and may have a little more experience that's all. I'm certainly no expert but I like to help. Dave Quote Link to comment Share on other sites More sharing options...
Mallette Posted March 7, 2014 Author Share Posted March 7, 2014 Help definitely appreciated! I'll re-install this weekend and see if I can get to the correct contacts to test. Do I assume: 1. J1 pin 6 to pin 7 and J1 pin 6 to J2 pin 1 2. 0 power off, 24v on power up. 3. What pins will show something to indicate the relay is open? 4. What should "open" read? Dave Quote Link to comment Share on other sites More sharing options...
babadono Posted March 7, 2014 Share Posted March 7, 2014 Help definitely appreciated! I'll re-install this weekend and see if I can get to the correct contacts to test. Do I assume: 1. J1 pin 6 to pin 7 and J1 pin 6 to J2 pin 1. These are the pins that should read zero ohms when board is out of unit. When you re install they become superflous. You will check the relays operation right at the output jacks. 2. 0 power off, 24v on power up. This is the DC voltage on the coil of the relay, probably most easily measured across CR4. It may not be exactly 24v when on as the driver circuitry may drop a little of the voltage so let's say greater than 20v. 3. What pins will show something to indicate the relay is open? Refering to post 20, with the power off you should read zero ohms across the output jack center conductor to shield. Upon power up and after the delay time,whatever that time is, you should read an open, this is with no inputs or outputs connected. 4. What should "open" read? Good question, as DJK stated depends on your meter. Let's test it. Turn your meter on, select the ohms function. Don't connect the test leads to anything not even each other. This is then definitely an "open" circuit. What does the display on your meter indicate under these conditions? OVER? OL? OPEN? Or just a flashing display? I've seen them all. Maybe yours has something different that I've never seen? Now connect the test leads together. This is definitely a "closed" or "short" circuit and your meter should display close to zero ohms. Dave Quote Link to comment Share on other sites More sharing options...
Mallette Posted March 7, 2014 Author Share Posted March 7, 2014 Thanks. Will give it a shock, er, shot, this evening... Dave Quote Link to comment Share on other sites More sharing options...
babadono Posted March 8, 2014 Share Posted March 8, 2014 Dave, Nothing bad is going to happen. Just be careful around the 120 volt side of the power supply and keep your wits about you. Eric Quote Link to comment Share on other sites More sharing options...
Mallette Posted March 8, 2014 Author Share Posted March 8, 2014 Roger that, Eric. Didn't happen this evening for a variety of reasons. Will give it another shock tomorrow... Dave Quote Link to comment Share on other sites More sharing options...
babadono Posted March 9, 2014 Share Posted March 9, 2014 Dave, I too have been busy until this beautiful Sunday morning. I will check again later if you've made any progress. Eric Quote Link to comment Share on other sites More sharing options...
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