RTD PT100 connection options

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kokonutz

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My understanding is that the XLR connector is what most use for attaching the Thermocouple to the control panel box. I happen to have an RTD PT100 with three wires. However, I'm also realizing that XLR jack/connector would require soldering...is there another option? I don't have soldering equipment, and I only need to do one connector. That said, could I just get a cable like this , cut it in half, wire one part to the coupler ends, and the other cut end to the PID - then just have the female-side pigtail out of the control box?

1614893347009.jpg
 

RedRyderr

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Not sure if this would work for you, but this is what came with my RTD probe when I bought it. It had the wires already soldered on the XLR female connector. Soldering iron isn't too expensive to buy though, if you want to learn a new skill :)

 

Beer4All

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The connector on the RTD is not an XLR type. A lot of people use the XLR fittings as a bulkhead connector for their panel. Use can use the XLR plugs for the plugged splice in the middle as you drew above but you will have to splice the RTD wire cable to one side of the XLR connectors. I would buy some heat shrink to go over your XLR to RTD cable splices and the RTD cable plug to the RTD itself. They are not water tight. You will need to be careful with the butt splice of the RTD to XLR cable in the middle, these are very small wires.

How are you planning to run the cable into your PID controller? Drill a hole in the enclosure and run it through?

I have the same type of RTD probe on my setup with the soldered bulkhead connectors. bought the DIY kit from Kal at the Electric Brewery.
 

RufusBrewer

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Looking at the drawing in the OP, my concern is the point that cable passes through box. What is the hole that the cable passes through? That is a point of failure waiting to happen. The cable wil be moved and rub against the edges of the hole. Either you clamp it down, but that can leadt to problems. If it is loose, then you run the risk of the cable getting stressed and pulled against connection point at the pid.

The best solution is to put a connector on the panel. Install a mating connector on the temp probe cable and you will minimize all your problems.

I can highly recommends the Neutrk brand of XLR connectors. (this is the connector virtually evey microphone uses) They make a good strong solid connection. They are of a size that is easy to work with, the solder cup termination make for an easy for the novice/beginner to solder. The strain reliefs on the cable connector are robust and reliable.

When money is not a factor, you can buy a spare temp probe, solder a connector on it, and in the case of failure, a repair is a minute or two away...
 

LarMoeCur

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I'd say it really depends on how your system will be used. I built my system to be mobile, meaning I can move it around for use and moving back to store in my garage. Like beer4all said those cables are super fine and very fragile.

If your planning on leaving your system fully connected and not move it around. I think you will be ok just splicing the wires together. I would for sure do a double heat shrink wrap to reinforce the spliced area.

Now on the other hand if your planning on moving the system around. You will need a better way to then a splice to keep your cables intact. No better way to ruin a brew day then trying to find a short in a RTD cable. You will know when it happens your HLT or Mash will be reading 853F or -25F. Then the dick dance starts! Soldering the connection or soldering on a quick connect is really the best way.

Harbor Freight has soldering irons for 5 bucks. Well out weights the cost of a replacement cable.
 

Beer4All

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Looking at the drawing in the OP, my concern is the point that cable passes through box. What is the hole that the cable passes through? That is a point of failure waiting to happen. The cable wil be moved and rub against the edges of the hole. Either you clamp it down, but that can leadt to problems. If it is loose, then you run the risk of the cable getting stressed and pulled against connection point at the pid.

The best solution is to put a connector on the panel. Install a mating connector on the temp probe cable and you will minimize all your problems.

I can highly recommends the Neutrk brand of XLR connectors. (this is the connector virtually evey microphone uses) They make a good strong solid connection. They are of a size that is easy to work with, the solder cup termination make for an easy for the novice/beginner to solder. The strain reliefs on the cable connector are robust and reliable.

When money is not a factor, you can buy a spare temp probe, solder a connector on it, and in the case of failure, a repair is a minute or two away...
I'd say it really depends on how your system will be used. I built my system to be mobile, meaning I can move it around for use and moving back to store in my garage. Like beer4all said those cables are super fine and very fragile.

If your planning on leaving your system fully connected and not move it around. I think you will be ok just splicing the wires together. I would for sure do a double heat shrink wrap to reinforce the spliced area.

Now on the other hand if your planning on moving the system around. You will need a better way to then a splice to keep your cables intact. No better way to ruin a brew day then trying to find a short in a RTD cable. You will know when it happens your HLT or Mash will be reading 853F or -25F. Then the dick dance starts! Soldering the connection or soldering on a quick connect is really the best way.

Harbor Freight has soldering irons for 5 bucks. Well out weights the cost of a replacement cable.
I agree with both you guys. Using the XLR connectors as a bulkhead is best practice for sure. I was able to solder the XLR bulkhead soldering cups as a first timer! [I heated up one of the pins so hot it actually moved on me lol! but it still works. Maybe buy one extra to practice?]. Give it a try...it is not a huge investment if you mess up compared to other things in the control panel or brewery.

Will the OPs idea work...yes but there is a higher probability of issues (troubleshooting time &/or issues during brew day) like RufusBrewer & LarMoeCur mentioned.
 

LarMoeCur

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I heated up one of the pins so hot it actually moved on me lol! but it still works. Maybe buy one extra to practice?]. Give it a try...it is not a huge investment if you mess up compared to other things in the control panel or brewery.
I had at least one pin in all three of my connectors move. I just slid it back into place. As long as the solder is good it should never be an issue. I call all of my solders, Gorilla solders! Big, Strong, and Ugly!
 
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