Changing original 32Amp contactors for solid state relays?

[Yonny24]

Could you please send me a photo(s) which shows the current upstairs control wiring?

hmm odd the fpg images are not uploading tonight. I'll try again later
"The uploaded file was not an image as expected."

 

[Yonny24]

Are you able to attach any jpeg photos? Maybe a glitch on the forum? Very odd

 

[marconi]

I think you should be able to open this attachment.

 

[Yonny24]

Hi Marconi,

Hope this works as I've been unable to upload any more photos which is odd. Maybe a limitation on my account? Used an image sharing site for these.
Think I will need to draw a diagram as its such a mess in here. Put some tape around a couple of cables just to label them

 

[Yonny24]

I'll get a drawing to you later once I have a moment to remove the plastic panel cover to check again. In the meantime I've set up a nice automation server on a docker. Some scripting with the sensors and works brilliantly. So many options here.

 

[Yonny24]

Hi Marconi.

I believe this is how they have wired it. 2 of the UFH zones are tiny (1m2) bathrooms so use very little. Not 100% on the middle UFH but looks like they share the same cables.

 

[marconi]

Hello. What I cannot gauge from the photos is how much space is available on the DIN rail to clip on new double pole contactors. The space available for the new ones determines how many separately controlled zones can be configured. Could you have a gander and tell me please?

 

[Yonny24]

If I remove the old timer on the left and move the cbs to the left I have about 22/23 cm to play with. Would like to have the one power meter in there (about 1cm wide) measuring all the kWh used by all the combined UFH zones. Good up to 40amps.

I'd be happy if I could just separate the last 2 UFH zones on the right.

Many thanks

 

[marconi]

I'll think about it tomorrow.

 

[marconi]

A standard DIN module is 17.5mm wide. So with two power meters that is 35mm - one for L1 and one for L2. Which leaves 220-35 = 185mm

A double pole 20A ABB contactor is a standard DIN module -the spec says 18mm. So you could fit in up to 10 of them.

ABB ESB20-20N-01 - https://new.abb.com/products/1SBE121111R0120/esb20-20n-01-installation-contactor

Could you have a think about how you want the zones arranged knowing that you have room for circa 12 standard DIN modules - and do you want a power meter for each zone?

 

[Yonny24]

A standard DIN module is 17.5mm wide. So with two power meters that is 35mm - one for L1 and one for L2. Which leaves 220-35 = 185mm

A double pole 20A ABB contactor is a standard DIN module -the spec says 18mm. So you could fit in up to 10 of them.

ABB ESB20-20N-01 - https://new.abb.com/products/1SBE121111R0120/esb20-20n-01-installation-contactor

Could you have a think about how you want the zones arranged knowing that you have room for circa 12 standard DIN modules - and do you want a power meter for each zone?

Hi Marconi,

I will visit my local home department store to see what they have available in terms of contactors first. We don't always have a wide selection of products and can be pricey.

I should be able to fit a new neutral cable into one or 2 of the rooms as you mentioned earlier to separate the 2 bedrooms but the rooms further away could be problematic if I need to fit more cables. I've had issues trying to get my fishline down some of the conduits. Quite a spaghetti junction! Took me 2 days to get the cat6 from my office down to the living room!

I'll get back to you.
Thanks very much for all your time on this.

 

[Yonny24]

Sorry been absent for a while. Worries with work and the pandemic etc.
Been difficult to find suitable contactors at a reasonable price. Found some 4 pole contactors. Shouldn't be any issue swapping 2 x 2 pole contactors for 1 x 4 pole should it? 2 live and 2 neutral inputs and outputs. Each 2 pole is only drawing about 10 amps. The 4 pole is a a 40amp.

Thanks

 

[marconi]

The 4 pole sounds fine. If you send me its details I will give it the once over.

 

[Yonny24]

The 4 pole sounds fine. If you send me its details I will give it the once over.

I believe it is the same one as this:

CONTACTOR MODULAR 4P 40A 230V MC1-40 – Castells online

www.subastasclick.com

Many thanks

Was going to leave it for this year but the buzzing from the downstairs is really quite annoying now as we have the heating on more frequently as winter is approaching here in the Southern Hemisphere.

 

[marconi]

I cannot read the make - what is it?

 

[Yonny24]

I cannot read the make - what is it?

Can't find much info on it but the listing says 'Carfil'. CF2804

 

[marconi]

At first blush they look rather cheap and cheerful. Here is a proposal: I will send you some ABB silent relays and perhaps you will make a donation to a children's charity in Uruguay akin to the UK's NSPCC - what say you?

 

[Yonny24]

At first blush they look rather cheap and cheerful. Here is a proposal: I will send you some ABB silent relays and perhaps you will make a donation to a children's charity in Uruguay akin to the UK's NSPCC - what say you?

Wow really appreciate the offer. Very kind of you indeed.

Unfortunately, the customs rules here are very strict and could end up paying a fortune in taxes and import duty fees requiring proof of purchase etc. List goes on of extra costs on top of the 60% tax.
This is why even cheap chinese goods are expensive here.

I'll probably just go for this model and try one first.

Kind regards

 

[marconi]

I understand. I will do some research tomorrow morning over a coffee. At 10 A and rated at 40 A they are most likely suitable - but I thought you wanted quiet contactors(*)

I, and maybe many others, have a bit of a downer on Chinese products at the moment if that is where this contactor is from. I find Italian made stuff good value - but then I have Italian ancestry with the surname 'Solari' - so I may be biased ;-)

* - We could try to be clever and put good but noisy contactors inside soundproofed enclosures? I'll have a look at materials and ways to attenuate the annoying hum. At first pass I wonder about some lead and rubber combination.

 

[Yonny24]

Yes I would prefer fairly quiet contactors. Not sure how much noise these would make tbh.

One out of the 3 downstairs is really buzzing loudly (the buzzing varies from day to day, from quite loud to a sound like its vibrating out of the module box), obviously not very well.

As you know the one upstairs is a 4 pole ABB and you cannot hear it at all. Super silent.

I have asked the supplier how much noise they produce.
Update: He's just replied and said they are not quiet.
[automerge]1591897472[/automerge]
oh look in this moment new models have appeared online.

Steck

STECK. E tudo se liga!

www.steckgroup.com

Interruptores Contactores | MercadoLibre.com.uy

Descubrí los productos más buscados que no te podés perder en Interruptores Contactores ✓ Con Envío Gratis y Rápido ❤ Aprovechá Compras Internacionales.

articulo.mercadolibre.com.uy

 

[Yonny24]

The seller of Steck has confirmed they are quiet and do not emit the same noise as the conventional contactors.
[automerge]1591901389[/automerge]

The seller of Steck has confirmed they are quiet and do not emit the same noise as the conventional contactors.

https://www.steckgroup.com/assets/uploads/produto_categorias/328/documento/CONTACTOR_MODULAR_11-03-2020_ES.pdf

 

[marconi]

Remember to switch off all the electricity and check everything is dead before you work on the swap. Label up the wiring too so the pairs are identifiable and recorded somehow near the contactor. Last, all connections must be tight and use all the strands of the conductors without any of them showing outside the entry to the terminal channel. Then it will nearly be as good a job as done by DPG ( ) - but only nearly so don't get carried away. Let us know how you get on - pictures are always good if you want your work checked and assessed.

 

[Yonny24]

Remember to switch off all the electricity and check everything is dead before you work on the swap. Label up the wiring too so the pairs are identifiable and recorded somehow near the contactor. Last, all connections must be tight and use all the strands of the conductors without any of them showing outside the entry to the terminal channel. Then it will nearly be as good a job as done by DPG ( ) - but only nearly so don't get carried away. Let us know how you get on - pictures are always good if you want your work checked and assessed.

Thanks will do.

Just purchased 3 of them. Got some 4mm wiring also to replace the 2 x 2mm wiring.
One of the 3 old ones was vibrating so much this morning I had to turn it off as my son was having a zoom school class and was interfering with his class! (home schooling still continuing here in Uruguay)

 

[Yonny24]

Arrived and all installed. Nice and quiet finally. Switch quietly and silent. Brilliant. Thanks for all your help

 

[Yonny24]

The UFH heating is cleverly connected across L1, L2 and N as shown in the diagram below. The black bar above the 5 cbs confused me; the voltage measurements clarified the situation.

Sometime please tell me L1 to L2 voltage. I am pretty sure you have a 3 phase supply arranged as I have drawn.

Otherwise I would swap the contactors for silent ones. Solid state switches can fail short-circuit which would not be a good thing so don't fit them. They also need substantial heatsinks and ventilation around these because they would get too hot without. If it was me I'd buy silent contactors. The three sets of UFH are each protected by a 20A cb. A 32A contactor is beefy enough to carry up to 20A 'all day long' and be more reliable than one rated close to 20A. Space the power meters and contactors apart so that there is some air movement and one does not warm the other.

Thank you for your patience!



Marconi

Hi Marconi,

Hope you are well.

Just revisiting this topic. Everything is running fine but had a doubt about the type of phase we have. The utility company changed our meter this week with a new smart meter after we had an issue with our bills after using the UFH (the clock was 4 hours out on the old meter so the cheap rates before 5pm were being calculated incorrectly!!)

From what I understood the 3 phase power set ups have 4 cables entering but single phase have only 3 (L1, L2, N).

You mentioned it was a 3 phase initially. Was it decided that this was a single phase in the end with L1, L2 and N?

Many thanks

 

[marconi]

Your supply is 'three phase 2 wire corner grounded delta' as in the diagram above but your line voltage is 225V (ish) instead of the 480V this diagram shows.

So in your home A is L1 and C is L2 and B is the earthed phase/line/neutral N.

Single phase supplies are derived by connecting between pairs of lines A-B, A-C and B-C.

Your UFH uses all these pairings to 'spread' the loading over the three lines/phases since this is a large long duration power demand and makes best use of capacity of the three lines to your home.

I did not delve into how all your other home final circuits are wired eg: lighting and sockets but I strongly suspect they are connected A-B thus L1-N, and B-C thus L2-N so that single pole switching may be used in the line/phase only because only L1 and L2 are at 225V wrt to N and E.... and N is at a low voltage wrt to E - I think we measured 20V ish.

When L1 and L2 are used the switching must be double pole as you have gathered from the contactor contacts wiring for the UFH because both lines are at 225V wrt to N and E.

 

[Yonny24]

Hi Marconi.

I believe this is how they have wired it. 2 of the UFH zones are tiny (1m2) bathrooms so use very little. Not 100% on the middle UFH but looks like they share the same cables.

Hi again,

Revisiting this set up from upstairs. I haven't added individual contactors yet with new neutral cables splitting them up.

My question/doubt now is about the power meter I have installed.

I have the 2 inputs of the power meter fed from the CBS outputs #4 and #5. I thought this would measure only 4 of the zones.

The red led on the power meter pulses depending on the power going through it. Remains green when no power is going through it.

Now what I observed is that it measures power from all 6 zones here. The led flashes at different rates for each zone UFH tested independently.

Is this due to the way the three phase 2 wire corner grounded delta works, and is capable of measuring the power used correctly for all zones?

Thanks in advance

 

[marconi]

In order to measure the power consumed by each of the three UFH zones the power meters P need to wired in between the zones and the contactor C as I have drawn in my attached diagram.

The same holds for elsewhere in your home to monitor power consumption by each UFH zone. So you should revisit how the power meters have been wired in - I cannot do that for you because I can no longer open any attached images in previous posts.

The total power consumption of your home however is measured by two meters - you might have thought three were required. For a three phase three wire system only two meters are necessary; the total power consumption being the sum of the two readings. Blondel's theorem if you want to look it up. My second attachment shows how they are connected. Note how the two meters are both connected to the third line N/L3.

If there were three meters they would be connected as in the last drawing, one in each line and the meters then connected to a common star node. Simply by making one of the lines common to the power meters one of the three meters becomes superfluous and an economy can be made.

Blondel's theorem:

Blondel’s theorem | Power in Poly-Phase System | Electricalvoice - https://electricalvoice.com/blondels-theorem-power-in-poly-phase-system/

 

[Yonny24]

In order to measure the power consumed by each of the three UFH zones the power meters P need to wired in between the zones and the contactor C as I have drawn in my attached diagram.

The same holds for elsewhere in your home to monitor power consumption by each UFH zone. So you should revisit how the power meters have been wired in - I cannot do that for you because I can no longer open any attached images in previous posts.

The total power consumption of your home however is measured by two meters - you might have thought three were required. For a three phase three wire system only two meters are necessary; the total power consumption being the sum of the two readings. Blondel's theorem if you want to look it up. My second attachment shows how they are connected. Note how the two meters are both connected to the third line N/L3.

If there were three meters they would be connected as in the last drawing, one in each line and the meters then connected to a common star node. Simply by making one of the lines common to the power meters one of the three meters becomes superfluous and an economy can be made.

Blondel's theorem:

Blondel’s theorem | Power in Poly-Phase System | Electricalvoice - https://electricalvoice.com/blondels-theorem-power-in-poly-phase-system/

Many thanks Marconi.

I do have one doubt - the current set up I have to read the power seems to register power going through UFH 1 and 2 as labelled also which surprised me. I thought it would have only read power on the other lines to the UFH. In fact, it registers power for each UFH if turned on individually.

Is it giving me false readings set up this way?

Appears to read about 1.1 Kwh for the large UFH 1 and 0.2 Kwh for 2 (small bathroom 1.5m2) which I expected but as mentioned I would not have expected it to read any power for these 2 the way it is connected.
Rather confused.

Regards
[automerge]1595421683[/automerge]
Just going to double check my drawing later - see if I have identified the connections from and to the PM correctly.

 

[Yonny24]

If I do need the 2 power meters to measure accurately the 3 phase upstairs following the 3rd setup would this be the correct way to wire them up?

Still curious why my current one PM set up connected to just the L2 and N/L3 is measuring power for all 6 UFH zones.

Thanks

 

[marconi]

If you want to measure total power provided by the 3 phase 3 wire supply to all the UFH connected to a panel then use two meters as I showed in my second diagram ie: place the two meters between the main switch and the contactors. The input to one meter is L1-N and to the other L2-N.

If you want to measure the power consumed by an individual UFH zone (effectively a single phase circuit) then use my first diagram ie: place the PM between the output of the contactor and the UFH zone. The input will be one of these pairs L1-N, L2-N or L1-L2.

Be careful to use the correct terminals on the PM ie: Lin, Lout, Nin and Nout (though it is most likely Nin and Nout are the same node so it is immaterial which is in and which is out.

I cannot turn up the spec for the DM25S - do you have it?

If you wish we can arrange a zoom session if that would be easier for you.

Regards

Marconi

 

[Yonny24]

Sorry just posted and saw your post above as I'm reading through it now.

Perfect many thanks again.

I'll go for set up #2. 2 power meters between the CBS and contactor. Just need the total for all.
So my figures for the UFH#1/#2 are incorrect as I do not have L2 connected even though the PM shows some power feeding through it, possibly just a % of the total power. Did suspect the street side new meter was reading more KwH than I calculated when running the UFH upstairs. Downstairs is pretty much spot on.

Will purchase another PM.
[automerge]1595451726[/automerge]
I have found these specs (mine is the 40 amp version).

Model Number:
DM25S
Display Type:
Digital Only
Phase:
Single Phase
Measuring Energy Range:
0-99999
Accuracy Class:
Class1
Output Voltage:
220VAC,110VAC
Operating Temperature:
-25℃~+55℃
Dimensions:
DIN EN50022 Standard
Product Name:
Meter Energy
Width:
18mm (One Module)
Current Specification (A):
5(20),5(30)A,5(40)A
Frequency:
50-60HZ
Constant:
2000imp/kWh
Display Mode:
5+1 Digits Counter Display
Connection Mode:
Direct Mode
Standard:
IEC60253-21

 

[Yonny24]

Sorry just posted and saw your post above as I'm reading through it now.

Perfect many thanks again.

I'll go for set up #2. 2 power meters between the CBS and contactor. Just need the total for all.
So my figures for the UFH#1/#2 are incorrect as I do not have L2 connected even though the PM shows some power feeding through it, possibly just a % of the total power. Did suspect the street side new meter was reading more KwH than I calculated when running the UFH upstairs. Downstairs is pretty much spot on.

Will purchase another PM.
[automerge]1595451726[/automerge]
I have found these specs (mine is the 40 amp version).

Model Number:
DM25S
Display Type:
Digital Only
Phase:
Single Phase
Measuring Energy Range:
0-99999
Accuracy Class:
Class1
Output Voltage:
220VAC,110VAC
Operating Temperature:
-25℃~+55℃
Dimensions:
DIN EN50022 Standard
Product Name:
Meter Energy
Width:
18mm (One Module)
Current Specification (A):
5(20),5(30)A,5(40)A
Frequency:
50-60HZ
Constant:
2000imp/kWh
Display Mode:
5+1 Digits Counter Display
Connection Mode:
Direct Mode
Standard:
IEC60253-21

My previous drawing of the power meter was incorrect. The middle output of the CBS is the N feeding to the middle 2 inputs of the contactor.
I have swapped the power meter over to the other live and neutral to measure ufh 1 and 2 for now.

 

[Yonny24]

I suspected measuring the UFH #1 and #2 with the PM wired connected to L1 and N (as opposed to L2 and N) the Kwh is double than previously measured.

 

[Yonny24]

Left hand drawing is the proposed wiring for the 2 x PM's. With the N line going in and out of both power meters. is this correct according to your diagram? Right is original wiring.

Thanks

 

[marconi]

Yours will work but it is simpler to do it like my attached diagram. Add the wire I have indicated in blue to go to the link between the middle terminals of the CTR and remove the two I have indicated in white.

(A power meter needs to know the voltage which it obtains from the two inputs and the current flow between the line input and line output. This why we can dispense with the white wires.)

 

[Yonny24]

Yours will work but it is simpler to do it like my attached diagram. Add the wire I have indicated in blue to go to the link between the middle terminals of the CTR and remove the two I have indicated in white.

(A power meter needs to know the voltage which it obtains from the two inputs and the current flow between the line input and line output. This why we can dispense with the white wires.)

Many thanks Marconi.

I think I will do the same with the downstairs wiring. 2 x powermeters between the main CBS and contactors (currently have 3 after the 3 contactors). I really only need to measure the total going through the 3 phase wiring now. This way I can re-use one of the 3 PM's I have and install it upstairs. So I'll have 2 downstairs and 2 upstairs. Makes the wiring a bit neater also.

Have a good weekend

 

[Yonny24]

Many thanks Marconi.

I think I will do the same with the downstairs wiring. 2 x powermeters between the main CBS and contactors (currently have 3 after the 3 contactors). I really only need to measure the total going through the 3 phase wiring now. This way I can re-use one of the 3 PM's I have and install it upstairs. So I'll have 2 downstairs and 2 upstairs. Makes the wiring a bit neater also.

Have a good weekend

All completed this weekend. 2 power meters installed between the CBS and contactors downstairs and 2 upstairs. Working Perfectly.

Thank you very much Marconi!