Electrical Notes Janome Qmp16Su - Janome QMP16SU Manual

Electrical Notes Janome QMP16SU

The following will be seen if the machine is in good operational order:
• Test 1 LED goes on when one presses the Start button on the handlebars and goes off when one presses
the Stop button on the handlebars. This is the "Go" LED.
• Test 2 LED is the Stitch Regulation LED. It comes on when stitch regulation is selected and off when
manual mode is selected.
• Test 3 LED and Test 4 LEDs (Transmit and Receive) flash rapidly when the front display is connected.
They go off when the displays are disconnected and the control board will then make three beeps
indicating the machine has no control attached at the machine's front or rear display connections.
• Needle LED is off from when the take-up lever is up until the needle is down (BDC). The LED is on from
when the needle is down (BDC) until the take-up lever is up.
• Option LED turns on when the stitch regulation over speed alarm is turned on. The LED goes off if the
over speed alarm is turned off.
• HRTBT LED does a heartbeat flash when the processor is working.
• Speed LED flashes on the Control board and on the main shaft encoder board when the hand wheel is
rotated. It flashes 100 times per revolution of the hand wheel.
What does 18VDC do?
• 18VDC LED light ring for Janome QMP16SU
• 18VDC drives signal to motor driver (motor speed control)
What does 5VDC do?
• 5VDC practically does everything else, but see below for some specifics
• 5VDC drives the main Control board processor
• 5VDC powers the front display
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QMP16SU Service Manual