New dimmer not scanning

Before I send the dimmer back I want to see if there is something simple I have missed.

I have a new dimmer in a new installation. I cant get it to scan on the network (and hence I cant set it up).

The simplified network consists of a PCI, the dimmer and a network burden. I can confirm that the cables are OK as I can use them successfully on the other dimmer in the same configuration (no key input on the network). Toolkit has been re-started and the network re-opened to make sure that there are no "glitches" with c-gate.

I have powered it down and re-powered it, restarted toolkit with no affect.

The C-bus light never comes on at any time.

When trying to set it up using learn mode (after adding a key input into the above network), I don't get the usual lights flashing alternatively, but instead they both flash in unison very quickly (cant find what this means) - and I cant get it to learn at all. The Key input wont light up as part of the learn mode. I confirmed my procedure by trying it on a working dimmer with positive results.

Is there anything else I can try that I have forgotten?

Thanks

Mick

 

If In Learn, you do get the rapid flashing, look at the state of the "C-Bus" LED to determine the state of the internal burden in the output unit. If you have a hardware burden, it may be possible that the internal burden is also enabled, and while on a short network this should normally work, it is possible that the burden in the PC Interface might also be enabled, and three burdens would almost certainly degrade communications to the point of being marginal.

communications should improve if you disable the internal burden of the output unit, and you can do this by double clicking ANY channel button while in the rapidly flashing state in Learn. You should see the state of the "C-Bus" LED change each time you double-click.

Exit learn with the burden disabled and try again.

 

Thanks Don and Nick

Yes there is a power supply - in the dimmer (unless I have been supplied the wrong one) and yes power is available to the left hand side (and right hand side).

Not being able to establish comms makes sense. If I have the PCI - Dimmer - key input, I only see the PCI. If I move the dimmer to the end I see the key input (sometimes - sometimes not). This makes me think there is something wrong on the comms side. More often than not I only see the PCI regardless of what order everything is on the bus.

I have been using a hardware burden and I don't believe that he PCI has the internal burden enabled, but I will double check. I will try and disable the output burden as well as outlined.

What does the C-bus LED do to indicate the state of the internal burden - I don't remember reading about that anywhere.

Is there a document on all this trickery for learn mode anywhere. There used to be a guide with the output units when they were first released with learn mode, but I don't have them any more to refer to.

Mick

 

Hi Mick,

You can find documentation on the Learn Mode stuff in the training documentation available here

Paul

 

The Learn 'trickery' has always been there since Learn mode was first added to C-Bus, and though it may have been documented in the little leaflets that used to be supplied with C-Bus2 products, I think the description would have been simplified and could have lost this detail.

You don't have to be in the fast flash mode either, any double click of a channel key in Learn will select all channels and display the state of the burden on the C-Bus LED. This state is known as the 'revert to factory' state, and if learn is exited from this state, then every selected channel will be 'cleared' to a dafault programme. If you don't want to revert any or all channels, then just deselect all of them one at a time before exiting Learn.

When Learn attempts to get a network running, it will go through quite a complex sequence of establishing clock first then trying to fiddle with burden until communication can be achieved. It usually works, but in practice I find that very short networks (just a few metres of cable) with low capacitance sometimes just can't be resolved. You might try adding a bunch more cable and see how you go.

 

Thanks for the input.

Tried everything mentioned here (Except the extra cable length) and still could not get it to communicate. The C-Bus light is now on, but learn mode still flashes quickly.

I think it has a problem and I will send it back unless by some miracle I get it working over the weekend.

Thanks for the link Paul. I have the old V2 software manual which obviously does not cover learn mode. I did not think to look at the newer versions.

Mick