MULTISKAN RC and MS SERVICE MANUAL
The plate stepper drive electronics on MOTCU board consists of stepper
controller N1 and dual bridge driver N2. N1 is used in half step mode, pin
10
tied high. The step phase outputs are from pins
4,
6,7
and
9.
The outputs are
pulse width modulated to control the motor current. The PWMoscillatoroutput
can be checked from pin 1 of N1. The inhibit outputs for bridge driver, pins
5
and
8,
should be always high. When the stepper
is
running, the phase outputs
should show pulses, the length of which is controlled by the pulse width
modulation. If not, N1 is faulty. Faulty N2 may also excessively load the
outputs. If the outputs from N1 are okay, but there are not respective >20
V
output pulses from pins 2,3, 13 and 14 of N2, then N2 is faulty.
Finally, one of diode bridge
V4,
current sensing resistors R11 and R12 or the
stepper motor itself may be faulty.
PLATE STEPPER TIMEOUT
Reason:
Action:
Service:
If this error is reported after startup, the home position of the plate was not found
within allowed time.
If the error is reported when trying to measure, the plate did not arrive to first
column within allowed time.
See PLATE POSITION ERROR
If the plate does not seem to move pmperly, see also PLATE POSITION
ERROR.
If the plate seems tomove properly, the pmblemis in sensing the plate position.
With instrument power off, manually move the plate to the right handend of the
track. Switchon powerandobserve the plate.
If
the first movement is to theright
against the end of the track, plate home position sensing does not work. With
power on, manually move the plate away from the right end of the track while
observing the signal at pin 32 of Dl on MUSCU-RC board. The signal should
be low until the plate is about 1 cm from the right end.
If
not, Dl or one of the
hall sensors is faulty.
If the instrument starts up without error but drives the plate against the left end
of the track and gives this error when trying to measure, the plate position
sensing does not work. The position is sensed by a led sensor located below the
measuring circuit board. During actual measure the sensor is disabled so it
won't interfere the results. The enable signal originates from pin
9
of Dl on
Document Release Section Page
Labsystems
351/352-100-X 1
.O
*og
8
18
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
To Next Page
Loading...
