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Sooo it's default on restart isn't last setting or you increase output after startup?
Anyways the main problem is your light isn't designed to be dimmed the way you are dimming it.

There are Buck driver chips on the circuit board to keep current constant to a specific # of leds in a row.
Specifically a pt4115.
That chip is dimmable using pwm.-

Up to 45V input but rated 30v, dim by pwm 2.5-6V, up to 50kHz frequency.
Apparently also 2.5-5V on the dim pin works as well which would actually
give a way to test my "theory" on how to make it a normal light.

Current setpoint is I = .1/ Resistors
.4 and .43 Ohms assuming in parallel sets the current at 476mA which would make sense for
"3W" diodes in series (more than likely 6 in series w/ the 24v power supply)

If you want it to work correctly you need to somehow use the dim pin on the driver chip.
I know a repeat of what I said before but you are fighting an ODD design.

When used correctly TC's have a fairly reliable record.
My modified one to use the 5v pwm circuit lasted over 3 years before I upgraded to a Bluefish mini.
There may be something a real electroncs geek could dig out of the system and driverr spec sheet.

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