Can't get trailing edge mode on universal dimmer

I have a Universal dimmer L5504D2UP which is refusing to glow orange (trailing edge mode) while powering a circuit which consists of 4 atco possums each powering a twin 50W halogen downlight unit. Instead it glows Green (leading edge) and of course I get lovely buzzing sounds from the fitting when I dim the lights anything off 100% - (I am using Philips Masterline ES 30W bulbs which have been recommended by Clipsal as being very low in filament noise by the way).

Is there any way to force the Universal Dimmer to Trailing edge mode? Could it be going green (inductive) because of the number of transformers, or the length of cable?

I should also say that a separate channel indicator on the dimmer pak does glow orange as expected powering an incandescent circuit.

 

If the unit is running in leading edge mode then the unit considers the circuit it is trying to run as an inductive circuit. This could be because there are long cables or the cables are coiled somewhere in the run

Can you clarify your circuit loading? You say that there's 4 ATCO possums on the circuit, each powering twin 50W fittings, but the lamps are 30W, not 50W... is that right?

Have you done a test by swapping this circuit over with the one that you know works in trailing edge mode on an incandescent bulb? This would check for a fault in the dimmer circuit.

Something else you might like to try is connecting a Mains Rated X2 capacitor of approximately 100nF across the terminals of one of the transformers. This will increase the apparent capacitance of the load that the dimmer observes and may be enough to help it make the right choice regarding dimming mode.