Amcron Micro-tech 1200 with a D6304B2 board. Found fan seized. Un-siezed fan, Fanformer windings brown and when powering up it gets hot. Suspect short circuit. Disconnected output to main board and fanformer runs cool. Visual inspection found power supply components on main board capacitor C4 brown/burnt and has full continuity running through it.
I'm just wondering what the output of the secondary output should be on the transformer which powers the main board? I've measured around 24v AC on the red and blue wires.
Some say it should be 15v and others say 18v. Looking at a schematic from another Crown Amp with the same main board it says 24v. Bit confused.
Micro-tech 1200 Fanformer Output Voltage.
1 reply to this topic
Posted 07 February 2014 - 12:43 PM
It should be twice 24VAC, with reference to the white wire; It is then reduced to +/-15V via regulators. Note : a 24VDC is derived and used to enable the relays in MA amps. There is no relay in MT units.