Load shedder and temperature modules

Hi (again today),

An other problem to solve : I wish to use Velbus for switch ECO to CONFORT mode on 5 radiants. Each room has it own VMB1TS and I’ve 5 relays free (VMB4RYx2)
However, I’ve to keep my power consumption low enough to avoid disrupting (cut power of the whole house) and I’ve bought a load shedder (délesteur).
The signal of load shedder should cover any other signal but if my VMB4RY cut the signal to the radiant (through pilot wire (fil pilote)) the radiant couldn’t receive shedder signal and will stay in CONFORT mode.

How can I solved this ?

pilot wire 4 orders :

  1. ECO is 230V full sinusoidal phase (negative+positive)
  2. CONFORT is 0V (no phase)
  3. LOAD SHEDDER SIGNAL is 230V half positive phase
  4. other orders not important

Is my question clear enough ? :open_mouth:
Nobody has the same conditions ?

This system is only used in France, so it is not very likely that people will have exprience with this…

How do you manage electric convectors then? no GIFAM protocol?
How control temperature if not with pilot wire?

salut golfy,

quel delesteur? prix?ou?

Je veux bien en installer un ,ou se place til par rapport au vmb4ry?


Le délesteur est un délesteur 4 voies Schneider-Electric (e-catalogue.schneider-electr … e&page=C44)

Le problème est le suivant :
Si le délesteur détecte une sur-consommation, il envoi un signal pulsé 230V positif qui est reconnu par les chauffages avec fil pilote comme étant une demande d’arrêt.

Si je pilote le chauffage avec Velbus, soit j’applique 230V sur fil pilote = mode ECO, soit j’ouvre le relais (0V = CONFORT)

Or s’il faut délester, il faut que le signal du délesteur soit prioritaire mais il n’arrivera pas au radiateur si le VMB4RY est en coupure… et le disjoncteur EDF plongera la maison dans le noir.

je ne sais pas comment gérer cela. :unamused:

Can you make a simple schematic of what you have at the moment? From what I understand, the load shedder gives you a signal depending of what your load in the house is, right? Thus it will give you no signal when there’s not much load and a altenating positive signal when there’s to much load. If this 's the case then the solution is, as I think, quite simple. Connect the pilot wire to a relay with make/brake contact. Connect a full phase at the brake contact and the signal from the load shedder to the make.

But as I said before, I’m not formiliar with this system.

Hi Jeroends,

I’ve drawn this picture to help me how to manage my power consumption.

I can put an entry in load shedder or VMB4RY but HALT signal has to be main signal (the signal over others signals).

If VMB4RY relay is OFF, there is no signal wich is equivalent to CONFORT mode. ECO mode is -3°C and HALT mode is stopping heating.
Maybe I can use a VMB6IN to inform my Velbus that is has to switch ON the relay (I(ve one on my installation)…

Any idea is welcome :unamused:


Do i understand it well that you use the temerature sensor only as an day/night switch or do you intent to use it as an thrmostate?
if you use it as an day/night switch then i put your relaycontact in serie with your V1 or V2 contact of the load shedder. if you look at your load shedder you have a normal close, normal open and common. The normal close contact connection is at the left of V1/2. The normal open contact is inside the load shedder and the common connection is the other avaliable connection. You have to put your vmb1ry normal closed contact in serie with the normal close connection. the other side you connect to input connection of the load shedder.

hope this will help you.



Do i understand it well that you use the temerature sensor only as an day/night switch or do you intent to use it as an thrmostate? [/quote]

In fact, I would to monitor temperature only because 0,5°C of accuracy is probably less than numeric thermostat integred to radiators (few years ago, it was better but now, regulation is 0,2°C)… so let’s sensors out of the story for now :wink:

However, I would to control at least 4 zones : childrens rooms, friend’s room, bathrooms, parent’s room, other.
Each could have CONFORT when a person is in and ECO when sleeping or out.

Like my installation in 12KW and I’ve 8 radiators (8x1000W around) and my ground boiler could take 8KW, load shedder is the only way to save me :unamused:
When saying I’ve induction in my kitchen (up to 7kW), I know that you would open your eyes like this : :open_mouth: (“there are silly these french” like Asterix & Obelix).

[quote=“Stis”]hope this will help you.

Thanks for your help anyway :slight_smile:

how did you put your image in your text so i can send you the schematics to wire your system? if you want i can send it by email.

is it this that you mean?
The thermostat steers the extra relay so that you have a half positive sinus signal when the heating is off and no signal when the heating is on or off when the shedder decides to do so.


ah ok,
I see you mean something else…
What you can do is use the above schematic ans set the vmbts to a higher temperature than you need. In this case the thermostat of your heater will take over and just use the sleep and day mode of the vmbts (in sleep mode set the temp low enough).