Leading edge technology in dimmers?

Hey guys,

I'm in a bit of a fix. I have dimmable electronic transformers installed in a house that I would like to control with a C-Bus L5508D1A 8CH dimming module. However I cannot get information (web or otherwise) on the electronic transformers so I cannot ascertain if they are compatible with the dimming module.

They appear to be manufactured by 'dais', model no. DA-E60
Other information on the case includes:

Dimmable Electronic Transformer
20-60W/VA
Prim 240V~50/60Hz 0.26A
sec 11.4V~eff. 5A
cos(phi) = 0.98
SELV EQUIV

I understand all the data and just nothing on it seems to indicate if it is either a leading or trailing edge dimmable transformer. Would anyone know any way of finding out as I'm hoping to install the dimming module soon but don't want to install it if it wont work correctly. Is there any way it can be identified from the above information or some type of testing on a spare transformer that I have?

Also, if any of you would know, can you use the L5508D1A to dim a 240VAC flexlight (trademark). This is a striplight/ropelight. It is rated for 16.6W/m and is manufactured by Wide Loyal Industries.

I wasnt sure if this was a C-Bus hardware issue or if it should be in the other hardware thread. However my apologies if I have it in the wrong place. Hoping someone can help me out.

thanks

rob

 

Typically when the manufacturer says that an electronic LV transformer is 'dimmable' they mean that it is dimable by either leading or trailing edge dimmers. If it is only dimmable by trailing edge dimmers conventionaly the manufacturer will say 'dimmable with trailing (or lagging) edge phase angle control dinmmers only. But this is a convention not a rule or requirement.

However as has been often noted on this forum, just because an electronic transformer can be dimmed by a leading edge item doesn't mean there are no cautions, most LV transformer manucaturers meet the EMC (electrnic noise) requirements for their products by placing a relatively large capacitor directly across the 240 (or 120V) input to the transformer, this causes the TRIAC or FET in the dimmer to 'see' a short circuit momenterily every half wave, the surge of current this causes can make the dimmer run hotter than the nominal load would suggest, depending on the design, make and manufacture of the transformer the value of this 'input capacitance' will vary and you may not be able to run the dimmer channel at its maximum Wattage rating if the transformer you have has an input capacitance towards the top of the range.

Get the info from the manufacurers and check it against the table of electronic transformers on the C-bus web site.

 

Just to add to what Uncle Sam said...

If in doubt, always use Trailing Edge Dimmers with capacitive loads (electronic transformers).