CM67 Optimum Start algorithm

Page 3 of 6  


Er no. You take away the power and it says at the position it was when power was taken away (de-energised)

That is true, but they are accurate enough once settled. That is why there is a 0-10v (simulated proportional feedback) version, so the controller knows exactly where the valve is.

It appears to have two coming out of it in some diagrams, but on read some more in depth data it will not modulate a valve. That is why L&S stuff is much superior.

A waste of time now, now the cm67z is here.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It is pretty obvious that the damn thing will stop when the power is removed because it has only three wires and no separate source of power.

Nope. The (temperature) controller does not know where the valve is directly at all. There is separate motor control electronics in the valve head, and that has feedback locally about the motor position. The effect of this is that the actuator position is more accurately repeatable from an applied voltage on the control input but there is still no direct feedback regarding the motor position to the temperature controller. However the arrangement is much more accurate than one with simple on/off/reverse control which relies on the assuming speed of movement of the actuator

Which is what I said in the first place.

system does and more.
Each room has temperature sensing leading to a central control system and then there is individual control to each radiator valve.
The CM67z system is interesting, but each controller only manages two zones so it is going to get expensive to implement. Since each TRV requires 2xAA batteries (not a lot of power available) it is going to keep Duracell sales quite buoyant....
.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

A controller acting on a 3 position actuator would pulse it one way or the other (a pulse to not 6 minutes as you mistakingly believe). In short, it nudges the valve one way or the other to reach setpoint. Some controllers can be used with any 3 position actuator of any make. It doesn't need to know the speed of the actuators travel. Simulated proportional feedback are more suited to PID controllers.

No, throw it all out and get the cm67z

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I didn't believe that at all, you did.

The L&S one certainly does, and any controller working in this way will need to know the speed of travel at least approximately, or as a loop there would be far too much or far too little gain. The data sheet for the L&S controller certainly refers to a range of speeds of actuator

I don't think so. I am doing some far better things and have some original ideas that I'm working on. I won't discuss them here though..

.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

You said a pulse can be minutes long. Duh!

I'll let you into a secret. These controllers have adjustments on them.

No. You will F**k it up. Throw it all out and get a ready made solution. Stop trying to be a controls engineer, when you clearly have missed the basics.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It can. It can be days or even months. The only criterion is that it goes on and off.

Some fairly crude ones, and I can read at least as well as you can, the difference being that I understand what I read.....

I don't think so. Already working and there are some interesting ideas which are commercially exploitable so I won't be discussing them here as I said.

an honours degree project and subsequently commercially for various industries for more than 10 years after that.
.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Not so.

But you have absolutely no experience whatsoever of them.

Not so.

Such as what? Electric valves on a rad with a central controller? Not new at all. The Honeywell RF system is the best in principle as there is no wiring. Or are you going to sell snake controllers?

This have moved on since then and you are clearly way behind.

Who?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

From the data sheet, the adjustments are quite crude in their effect simply because the device being controlled is crude in nature.

As I said, there are some commercially exploitable things in what I'm doing, so I won't be going into detail

Basic principles of control mathematics don't change. Their practical application certainly does and I have some interesting new concepts that I am developing.

.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Nope.
Nope. You need either two signals driving a motor one way or the other, or a short cycle time pulse controlling some electronics hooked up to the motor.

In a form that could be controlled by a single output pulse switch controller like a CM67 they don't exist......

.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote in message

The cm67 can't modulate, tat is why it is best to go for a good L&S model that can and have finite temp control.

All snakes should be killed, especially the poisonous ones.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Which is what I said in the first place.

.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

You never mentioned L&S. You never knew of their controllers.

No. Poisonous snakes are no use whatsoever and kill people.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

L&S was never the subject of the thread. You introduced it because you had painted yourself into a corner with respect to the CM67.

even those that are are seldom aggressive towards humans.
Of course if you're a rodent, then that's a different matter, whether you can tango or not...... cha cha cha doesn't help either.. ;-)
.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

The thread had moved to finer temp control via modulation. Better choice is a heat bank, using a cheap simple condensing boiler and a 3-way mixing valve from a L&S controller for the heating off the heat bank.

Do you feed this reptile live mammals?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

You moved it to that discussion because you got out of your depth with respect to the CM67 by trying to be clever and falling on your face. You then proceeded o compound the issue by using your normal tactics.
Actually the discussion about snakes is quite apropos. They slither around as well.

.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Andy you are clearly bitter and twisted. You never thought of this brilliant simple method

Andy, you being a snake aficionado will know about slithering from close quarters.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

actuators that I am surprised that there are still products on the market using it.
.andy
To email, substitute .nospam with .gl
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
You were on about individual radiator electronic control:
http://europe.hbc.honeywell.com/products/docs/CMZONE.html
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I was just looking at these a few minutes ago, but I can't find a supplier or pricing info. Any ideas?
Neil
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.