Toledo Transducers MoniTTor N269, Installation And Operation Manual

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located in the lower middle section of the main PC board. There are two rows of pins:
the front (lower) row of pins is the analog output for the channels starting with channel 0
at the left end; the rear (upper) row of pins is the signal ground. These pins are such that
scope probe may be clipped to the pin or a mating connector may be attached to all pins
for sending the signals to a recorder, etc.
The signal level is 0 volts when the channel is balanced to zero in the no-load condition. A
capacity load represents a positive change of 5.0 volts. The output impedance is 1000
ohms. Due to temperature changes in the sensing devices the no-load signal will drift
causing small shifts in the output voltage at the output jacks. The span, however
(5.OV=capacity), will remain constant.
B. SYMPTOMS AND SOLUTIONS
DISPLAY WILL NOT LIGHT
1. Check AC power to meter - 115VAC +-15% 60Hz.
2. Check fuse
3. Check for loose cables between chassis and display board, etc.
4. Check DIP switch and jumpers on keyboard
5. Check DIP switch and jumpers on main board
6. Check power to PC boards - +5VDC, +-15VDC, +-12VDC
MEMORY LOST WHEN POWER LOST
1. Check battery - loose? or bad (must be greater than 2.5 VDC)
2. Check 50 pin ribbon cable from power PC to main PC
V. N269 SERIAL COMMUNICATIONS PROTOCOL FOR COMPUTER
INTERFACING
A. HARDWARE CONNECTION - See installation instructions