Leica WILD M695 Service Manual page 36

Service manual M695
Doc code 636 718
5V supply
Receiver board
PGND, SENS and logics
ground
SENS
An LED on the function display shows 5V OK. The following are supplied
with power: Handswitch or f&switch, and logics on receiver board.
Microscope ground (PGND) and SENS are connected in the microscope. The
high lamp current produces a voltage drop of about 0.6V at PGND. This
voltage is passed to the control unit through SENS.
For the reason indicated above, Logic ground is about 0.6V below PGND in
the microscope. The voltage drop at PGND influences the level of the control
signals.
All control signals to the microscope are measured with the testbox in relation
to SENS. SENS is connected to GND trough a 20-Ohm resistance at panel
board.
Description of control unit MEL64/65
09/93 3077-HWE
5-7