Janome Quilt Maker Pro 18 VERSA - Indications of Speed;Needle Position Sensor; Sensor Composition and Function; LED Indicators for Sensor Operation

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Quit Maker Pro 18 VERSA
Indicaons of Speed/Needle Posion Sensor
The main sha speed and needle posion sensor
mounts to the main sha near the back hand wheel.
It is composed of a disk with two encoder regions.
The outermost region consists of 100 small segments
to provide speed feedback to the control system. The
inner region consists of only two segments (an “on”
region and an “o” region).
There is a forked circuit board containing an emier
and a receiver for each of the two encoder regions.
With the front cover open and the power and control
board hooked up and powered on, you can rotate the
hand wheel and see the green LEDs ash to indicate
that the encoder is working properly.
The green “Speed” LED on the le side of the board
should ash on and o at a rate of 100 ashes per
revoluon as you rotate the hand wheel. The green
“Needle” LED on the right should turn on to indicate
the needle is in the “Up” posion (the take-up lever
is in its highest posion) and turn o to indicate the
needle is in the “Down” posion.
Careful inspecon of these LEDs as you rotate the
hand wheel with the power on will tell you whether
the encoder is funconing properly. Damage to the
encoder disk or any build-up of dust, oil or other
material can impede the transfer of light through the
transparent poron of the disk and cause the encoder
to miss some pulses.