Janome Quilt Maker Pro 18 VERSA, Руководство по обслуживанию

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Quit Maker Pro 18 VERSA
Indications of Speed/Needle Position Sensor
The main shaft speed and needle position sensor
mounts to the main shaft 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 “off” region).
There is a forked circuit board containing an emitter
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 flash to indicate
that the encoder is working properly.
The green “Speed” LED on the left side of the board
should flash on and off at a rate of 100 flashes per
revolution as you rotate the hand wheel. The green
“Needle” LED on the right should turn on to indicate
the needle is in the “Up” position (the take-up lever
is in its highest position) and turn off to indicate the
needle is in the “Down” position.
Careful inspection of these LEDs as you rotate the
hand wheel with the power on will tell you whether
the encoder is functioning 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 portion of the disk and cause the encoder
to miss some pulses .