Equipment for New Build

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Here are some pictures. As you suspected, there is no RS-485 connected to the heater. What's odd is when I look closely at the picture, it definitely looks like 3 of the screws have been used. So he likely had it connected via the RS-485 prior to yesterday? If that's the case, why would he change it? The PB company owner replied to my text this morning saying they would be getting a Pentair rep involved next week. I don't think their installer has much experience with these IntelliCenter systems.

mastertemp_control_board.jpg

intellicenter_heater_config.jpg
 
I would make the RS-485 connection and get it working and tell the builder thank you, it is working now and please have your installer not touch my equipment again.
 
ajw22 said:
I would make the RS-485 connection and get it working and tell the builder thank you, it is working now and please have your installer not touch my equipment again.
Click to expand...

That's what I'd like to do. How do I get my hands on an RS-485 cable so I can get this fixed myself?

The tricky part is asking the PB to not have the installer come back even though I was told he would be the one handling any warranty issues with the equipment. At a minimum, I will be telling the PB to never touch the equipment again without me being present. I was nervous leaving for work yesterday not knowing what he was doing and here we are.
 
Any 3 or 4 wire cable will work. Around 18 gauge.

If you have cat5 cable double up each pair to make a 4 wire cable.
 
With cat5e and above (FTP/STP), you get shielding which can help prevent data errors.

Outdoor rated is also a good idea.
 
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While RS485 is low bit rate, at a minimum it requires twisted pair wire. But I have found that shielding is necessary when you have a VS pump because it generates a lot of RF noise due to the PWM waveform driving the motor.

What is the distance between the two end points?

Amazon has quite a bit of shielded twisted pair wire for reasonable pricing but it depends on the length.

 
mas985 said:
While RS485 is low bit rate, at a minimum it requires twisted pair wire. But I have found that shielding is necessary when you have a VS pump because it generates a lot of RF noise due to the PWM waveform driving the motor.

What is the distance between the two end points?

Amazon has quite a bit of shielded twisted pair wire for reasonable pricing but it depends on the length.

Click to expand...
It’s a pretty short distance. See the below picture. I do have some CAT6 cable I could sacrifice. To be honest it’s infuriating that I’m sitting here trying to find a cable to connect my heater the correct way on a brand new build.

IMG_5567.jpeg
 

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I would use whatever you got to get it going.

You can always upgrade the cable in the future.
 
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mas985 said:
While RS485 is low bit rate, at a minimum it requires twisted pair wire. But I have found that shielding is necessary when you have a VS pump because it generates a lot of RF noise due to the PWM waveform driving the motor.

What is the distance between the two end points?

Amazon has quite a bit of shielded twisted pair wire for reasonable pricing but it depends on the length.

Click to expand...
I ordered the that CAT6 cable you linked to and it was delivered yesterday. As soon as it stops raining here I plan to go out there and try to get this thing connected. Is there anything I need to disconnect once I get the RS485 connection in place? How is the IntelliCenter communicating with the heater currently? I see the heater turns on when I call for heat but that's all it does (no power to the IntelliValve until heater powers on which is what I need to resolve).

Of course my wife is concerned that the PB might try to say I'm 'voiding my warranty' by trying to repair things myself but if they can't do this then what other options do I have?
 
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The only thing you need to make sure of is that you use a twisted pair of wires for the two data lines on the connector. I believe the differential data lines are the two middle connectors. The other two are ground and V+. V+ should not be connected (for remotes only). However, ground should also be connected between the two boards to maintain a voltage reference. I like to ground one side of the shield as well to prevent ground loops.

1716820613364.png


1716820199273.png
 
Normally, a heater does not require any type of communication other than a thermostat wire that turns the heater on and off. So I am not sure what the comm connection is needed for.
 
DSMinAtlanta said:
Is there anything I need to disconnect once I get the RS485 connection in place? How is the IntelliCenter communicating with the heater currently? I see the heater turns on when I call for heat but that's all it does (no power to the IntelliValve until heater powers on which is what I need to resolve).
Click to expand...

See post #70 where I explained how your current 2 wire control is connected.

You need to disconnect that and jumper the firerman switch connection in the heater to restore its power.
 
mas985 said:
The only thing you need to make sure of is that you use a twisted pair of wires for the two data lines on the connector. I believe the differential data lines are the two middle connectors. The other two are ground and V+. V+ should not be connected (for remotes only). However, ground should also be connected between the two boards to maintain a voltage reference. I like to ground one side of the shield as well to prevent ground loops.

View attachment 577521


View attachment 577512
Click to expand...
So something like this?

IMG_5575.jpeg
 
NO! Doing it that way eliminates the twisted pair which you do not want to do. Each wire of A twisted pair goes to each terminal. The differential signal must be carried over a single twisted pair.

Look at the diagram again:

1716822504630.png

1716822800644.png

So for example, the ORANGE wire would go to terminal #3 and the WHITE/ORANGE wire to terminal #2.

The ground doesn't matter. Any wire will do.
 
mas985 said:
NO! Doing it that way eliminates the twisted pair which you do not want to do. Each wire of A twisted pair goes to each terminal. The differential signal must be carried over a single twisted pair.

Look at the diagram again:

View attachment 577562

View attachment 577567

So for example, the ORANGE wire would go to terminal #3 and the WHITE/ORANGE wire to terminal #2.

The ground doesn't matter. Any wire will do.
Click to expand...
Ah now I see what you're saying. So you really do end up with a lot of unused wires with this CAT6. Thank you for the clarification!
 
Right, most of the wires are wasted but the cable is cheap anyway.

The receivers in RS485 are differential op-amps which have very high input impedance so there is very little current on those wires and voltage drops are not of any concern.
 
ajw22 said:
See post #70 where I explained how your current 2 wire control is connected.

You need to disconnect that and jumper the firerman switch connection in the heater to restore its power.
Click to expand...
Okay I just read your post #70 again and I realize I need to look for that connection where the power comes into the heater. I'll take a look at that next to make sure I'm following exactly. Then I'll need to construct a jumper since the PB removed the factory installed one. Might mean another trip to Home Depot today. I'll take another picture of that connection when I open it up.
 

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