satwar Posted July 31, 2020 Posted July 31, 2020 I am connecting a device which runs on 24 VDC and uses a third wire running from the device to ground through a switch to differentiate between ON-OFF status. I was planning to use a EZIO2x4 to connect +5 VDC terminal of EZIO2x4 to I2(or I1)+ and then connect third wire from the device's control signal output to terminal I2(or I1) -. Thanks in advance
Brian H Posted July 31, 2020 Posted July 31, 2020 (edited) Is the switch dry contact? Where both terminals are not referenced directly to the 24 volt supply? If the control signal switches to the 24 volt common or is +24 volts in one position and 0 volts in the other position. We may have to think on this a little more. Let us know if the third wire connects to the common 24 volt supply when activated. If the switch is a Dry Contact type. I2(I1)+ to EZIO2x4 5volts. I2(I1)- to one of the switches terminals. The other switches terminal to the EZIO2x4 GND Ground terminal should work. If the switch connects to the 24 volt common when On. I2(I1)+ to EZIO2x4 5 volts. I2(I1)- to the switches third wire for the switch. GND terminal on the EZIO2x4 to the 24 volt common should work. Edited July 31, 2020 by Brian H Change information.
Brian H Posted July 31, 2020 Posted July 31, 2020 If you want to totally isolate the input. As the EZIO2x4 can accept up to a 30 Volt DC input. I2(I1)+ to the +24VDC. I2(I1)- to the third wire that connects to the 24 volt common when On.
satwar Posted July 31, 2020 Author Posted July 31, 2020 (edited) Perhaps this picture will help clarify. It looks to me like I just have to run the control wire to the EZIO2x4 I2- terminal and secondly connect a wire from the EZIO2x4 +5 VDC terminal to the I2+ terminal. scan1.pdf Edited July 31, 2020 by satwar
Brian H Posted July 31, 2020 Posted July 31, 2020 (edited) You need two wires from the device to the EZIO2x4. If you are using the I2 inputs. +5 to I2+. I2- to the white wire on the device. EZIO2x4 GND terminal to the control circuits Black Common. Edited July 31, 2020 by Brian H
satwar Posted August 1, 2020 Author Posted August 1, 2020 Well I wasn't expecting that I'd have to run a wire tying GND to the black Common. Thank you so much Brian, this forum has some enormous talent. I didn't expect to get into such deep water. I think I've had enough electronics on this project.
Brian H Posted August 1, 2020 Posted August 1, 2020 The EZIO2x4's GND is the reference for its 5 volt power supply. It is an isolated ground for internal use. It does not connect to the ground on the power line input or any other ground. When you are using the switched output on the device you are using. You have to have its common connection for the output switch and the GND of the EZIO2x4 tied together so the switch can be read.
satwar Posted September 12, 2020 Author Posted September 12, 2020 (edited) Well I think I have it working. One circuit with supply +5VDC to I1+, then I1- to external dry contact to GND on EZIO2x4 Second circuit with supply +24VDC to I2+, then I2- to external dry contact to common wire The two circuits work independently, and work appropriately by displaying the status of EZIO2x4 Edited September 12, 2020 by satwar
satwar Posted September 16, 2020 Author Posted September 16, 2020 (edited) On 8/1/2020 at 6:30 AM, Brian H said: The EZIO2x4's GND is the reference for its 5 volt power supply. It is an isolated ground for internal use. It does not connect to the ground on the power line input or any other ground. When you are using the switched output on the device you are using. You have to have its common connection for the output switch and the GND of the EZIO2x4 tied together so the switch can be read. Looks like I don't have this problem resolved yet, and it seems that the reason may be that I didn't pay enough attention to your comment about the common wire. Are you saying I need to tie together the GND to the common wire (black wire in drawing). Sorry if this is tedious. Thanks again for the help. new device.pdf Edited September 16, 2020 by satwar
Brian H Posted September 17, 2020 Posted September 17, 2020 (edited) Not tedious. The attached New Devices PDF file shows. You have +24VDC from the device in to I2+ and the the White contact to the I2- connection. That switches to the devices 24VDC common. That should work fine. My comment on the GND was for using the modules internal 5 volt supply not the devices 24VDC supply. That may have muddled things. If you have the proper sensor reading you wanted to see. You are correctly connected. Edited September 17, 2020 by Brian H
satwar Posted September 18, 2020 Author Posted September 18, 2020 Well I put my best foot forward, and yielded the attached schematic. I've stared at these drawings for days. As a side note, I don't understand how the optical isolation works. I seems you connect to I2 + terminal and then to I2 - terminal and the isolation hpapens forum.pdfly ?
Brian H Posted September 19, 2020 Posted September 19, 2020 (edited) The schematic is correct. Using the +5V for sensing the I1 connections and the devices +24V for sensing the I2 connections. Isolated inputs use an opto isolator component. To completely isolate the modules electronics from the outside world. To turn it On. You have to put +5VDC to +30VDC to the +I1 or +I2 terminal and the -I1 or -I2 terminal to the negative of the supply. Through a switch in your application. The DC current through the isolator input. Tells the modules electronics the input is On. In your case I1 is using the internal +5 supply so you have the GND on the module switched on and off to sense I1 state. I2 in your case has the external devices +24VDC on the I2+ and the I2- switched to the 24 volt supply of the external device. When I mentioned the GND connection in an earlier reply here. It was when you thought you would use the +5VDC of the module for the external device on I2. Forget that as you are using the external devices -24volt common reference. The I3 AN1 and I4 AN2 terminals are connected to the internal electronics. They are not isolated to the outside world and could be damaged by voltages or spikes on them. They are also high impedance and can pick up stray AC hum. That is why some say ground them if not in use. Edited September 19, 2020 by Brian H Add data. Fix spelling.
Brian H Posted September 19, 2020 Posted September 19, 2020 (edited) Hope this may help. Though it may confuse things. The Isolated Inputs use a Opto Coupler for the input. It looks like a small 8 pin IC. When you put a +DC voltage on one of its + inputs through an internal current limiting resistor and a -DC on one its - Input. An LED inside the module turns on. The light from the LED turns on a Photo Transistor inside the coupler. That signals the internal electronics of the EZIO2X4 the Input is On. The External input voltage never gets directly connected to the EXIO2X4 electronics so it is isolated from the outside world. The Analog Inputs are directly connected to the EZIO2X4s electronics. So it can use a limited voltage range input and outside noise and garbage can get into it. Edited September 19, 2020 by Brian H
satwar Posted September 19, 2020 Author Posted September 19, 2020 4 hours ago, Brian H said: The schematic is correct. Using the +5V for sensing the I1 connections and the devices +24V for sensing the I2 connections. Isolated inputs use an opto isolator component. To completely isolate the modules electronics from the outside world. To turn it On. You have to put +5VDC to +30VDC to the +I1 or +I2 terminal and the -I1 or -I2 terminal to the negative of the supply. Through a switch in your application. The DC current through the isolator input. Tells the modules electronics the input is On. In your case I1 is using the internal +5 supply so you have the GND on the module switched on and off to sense I1 state. I2 in your case has the external devices +24VDC on the I2+ and the I2- switched to the 24 volt supply of the external device. When I mentioned the GND connection in an earlier reply here. It was when you thought you would use the +5VDC of the module for the external device on I2. Forget that as you are using the external devices -24volt common reference. The I3 AN1 and I4 AN2 terminals are connected to the internal electronics. They are not isolated to the outside world and could be damaged by voltages or spikes on them. They are also high impedance and can pick up stray AC hum. That is why some say ground them if not in use. Okay, thank you, I think I understand what you are saying and you are satisfied with the most recent schematic I've sent. Now that I have a blueprint to follow, how do you suggest that I troubleshoot to figure out what's going wrong
Brian H Posted September 19, 2020 Posted September 19, 2020 (edited) I missed the difference between the Devices.pdf and the Forum.pdf files. You had it correct in the New Devices.PDF and I thought you said it was OK. Go back and rewire it to the New Devices.PDF. Forum.PDF is wrong. I2+ to the RED +24V in the device. I2- to the White switched signal out from the device. Edited September 19, 2020 by Brian H
satwar Posted September 19, 2020 Author Posted September 19, 2020 (edited) 2 hours ago, Brian H said: I missed the difference between the Devices.pdf and the Forum.pdf files. You had it correct in the New Devices.PDF and I thought you said it was OK. Go back and rewire it to the New Devices.PDF. Forum.PDF is wrong. I2+ to the RED +24V in the device. I2- to the White switched signal out from the device. Sorry for the confusion, but I haven't had circuit 2 working, at least unreliable at best. That being said if you want me to rewire back to "new device.pdf" anyway, no problem, but we shouldn't go back under the mistaken impression that circuit 2 was ever working. As a test I rewired circuit 2 as circuit 1 and found that the alarm behaved correctly and alarmed for circuit 2. Most of the connections were tested with this test and all seemed to work, so I'm don't believe the problem is with the EZIO2x4. Edited September 19, 2020 by satwar results of swapping circuit #1 and circuit #2
ELA Posted September 19, 2020 Posted September 19, 2020 Satwar, With the new device wired as in the New Device.pdf - 1.Put the negative of your meter on the 24V (-) power supply terminal. 2. Put the positive of your meter on the I2(-) terminal. 3) Record Meter dc voltage with the new device turned off. 4) Record Meter dc voltage with the new device turned on.
Brian H Posted September 19, 2020 Posted September 19, 2020 (edited) 4 hours ago, satwar said: Sorry for the confusion, but I haven't had circuit 2 working, at least unreliable at best. That being said if you want me to rewire back to "new device.pdf" anyway, no problem, but we shouldn't go back under the mistaken impression that circuit 2 was ever working. As a test I rewired circuit 2 as circuit 1 and found that the alarm behaved correctly and alarmed for circuit 2. Most of the connections were tested with this test and all seemed to work, so I'm don't believe the problem is with the EZIO2x4. I thought you said input two was working when wired to the new devices schematic. In your September 12 post. Your Wednesday post must have been where you updated the status to not reliable. The wiring in the forums schematic will not work as both + and - 24Volts are needed on the I2 terminals. ELA gave you a great set to tests. If it worked intermittently meter tests of the On and Off voltages will give a good indication of what maybe the problem. Do you know if the switch in the device is a mechanical type. That sometimes can get intermittent? How far away from the EZIO2X4 is the new device and what gauge wire are you using? Edited September 19, 2020 by Brian H
satwar Posted September 20, 2020 Author Posted September 20, 2020 1 hour ago, Brian H said: I thought you said input two was working when wired to the new devices schematic. In your September 12 post. Your Wednesday post must have been where you updated the status to not reliable. The wiring in the forums schematic will not work as both + and - 24Volts are needed on the I2 terminals. ELA gave you a great set to tests. If it worked intermittently meter tests of the On and Off voltages will give a good indication of what maybe the problem. Do you know if the switch in the device is a mechanical type. That sometimes can get intermittent? How far away from the EZIO2X4 is the new device and what gauge wire are you using? The EZIO2x4 is approximately 40 feet from the new device, and using 18awg wire. The manufacturer says you can run the device 500 ft with 22 awg wire or 1000 with 18 awg for 1000 ft. Yes I thought the new device was running when I first installed but soon the signal became intermittent and lately doesn't run at all. I should also note that the device is very sensitive to outdoor temperature, and I haven't been able to keep the device cold enough to start running yet. The manufacturer recommends using some freeze spray., which I must purchase.
satwar Posted September 20, 2020 Author Posted September 20, 2020 3 hours ago, ELA said: Satwar, With the new device wired as in the New Device.pdf - 1.Put the negative of your meter on the 24V (-) power supply terminal. 2. Put the positive of your meter on the I2(-) terminal. 3) Record Meter dc voltage with the new device turned off. 4) Record Meter dc voltage with the new device turned on. I get 24 volts between 24 V - and I2- terminal with the device powered up but not sending an output signal. When conditions are right the device is supposed send an output signal, which in turn links to EZIO2x4 to update the on/off status. The device is very sensitive to outside temperature and I have to keep the device consistently cold before the device will operate. The weather is highly variable right now, which makes the testing very challenging. I'm on the hunt for some freeze spray to cool down to a consistently low temperature.
Brian H Posted September 20, 2020 Posted September 20, 2020 What is the device? I would suspect the device itself. If it need to be kept cold enough with freeze spray or it is intermittent or unresponsive at all. If the devices output is not a mechanical relay but a solid state switch. That could possibly be a factor.
satwar Posted September 20, 2020 Author Posted September 20, 2020 36 minutes ago, Brian H said: What is the device? I would suspect the device itself. If it need to be kept cold enough with freeze spray or it is intermittent or unresponsive at all. If the devices output is not a mechanical relay but a solid state switch. That could possibly be a factor. You know this may simply be a problem not getting the device consistently cold enohh
Brian H Posted September 20, 2020 Posted September 20, 2020 (edited) IMHO any device that has to be kept cold to work. Is poorly designed or defective. I personally would be returning it or asking the manufacturer to fix it right so it worked in normal temperatures and I don't need a constant spray of freeze spray to make it work. What are you going to do. Constantly spray it with freeze spray to get it's readings? When you want to use it. You also still didn't tell us what it is and what is supposed to be doing. Kind of hard to troubleshoot if you don't know what you are trying to diagnose. When you get your freeze spray and freeze it. Let us know what you find out. Edited September 20, 2020 by Brian H
satwar Posted September 20, 2020 Author Posted September 20, 2020 (edited) 19 minutes ago, Brian H said: Well any device that has to be kept cold to work. Is poorly designed or defective. I personally would be returning it or asking the manufacturer to fix it right so it worked in normal temperatures and I don't need a constant spray freeze spray to work. What are you going to do. Constantly spray it with freeze spray to get it's readings? When you want to use it. You also still didn't tell us what it is and what is supposed to be doing. Kind of hard to troubleshoot if you don't know what you are trying to diagnose. Yes I apologize for not revealing the device, because I didn’t want to get into side issues of how the device works. The device is a snow sensor which measures both air temperature (must be below 38 F) and moisture (snow flakes melting on sensor). The freeze spray is for testing purposes only. Once the device has been cooled down with freeze spray the procedure is to add a few drops of water to the sensor. You have been extremely helpful in learning how to configure the EZIO2x4. The only thing left to test is the sensor itself. Edited September 20, 2020 by satwar
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