Oval PG30D, Instruction Manual

Page: 4 / 12

T-518-9-E
103 102
116
119
139
Fig. 5 Fig. 4
167
Transmission gear box
PG30D PG30D
Fig. 7
Fig. 6
Shown in Fig. above is the setup for observing the
output pulse waveform. Couple the oscilloscope or
synchroscope across terminals and and monitor
the waveform while allowing the pulse generator to
revolve at a constant rpm. Connecting the multimeter
across terminals and enables you to make an ON/
OFF level measurement. However, you cannot make
a waveform ratio measurement with the multimeter
alone.
Waveform ratio is correct of H
1
＝ .5V ± 1V and H
＝ 1V ± 1V when C/D is somewhere between 1/
and /1. If a correct waveform like the one shown in
Fig. does not appear, replace the noncontact switch
unit with a new one in the manner outlined in the next
section.
0V SIG
DC
24V
510 Ω
D
20V
10V
0V
H
2
H
1
C
■
DISASSEMBLY AND INSPECTION
◎
The pulse generator should be disassembled for inspection once a year.
(Make sure that the transmitter cables are not lodged between the casing parts while reassembling.)
If there is no or few (or too many) pulses from the pulse generator although the flowmeter register pointer or
counter do move, the pulse generator is suspected for a fault. Inspect its components according to the procedure
described below.
1. Remove the pulse generator from the flowmeter.
Remove four screws (1) to gain access to the
transmission gear box. Check the transmission
gear box for any evidence of slippage or loose
crimping.
●
Monitoring the Output Waveform
. Remove four screws (19) holding the rear lid (10)
in place and remove the lid. Make sure to see that
the slit disc (11) turns freely and that the brake
shoe (119) works properly.
NOTES : 1. The same procedure applies to Model PG0DEP.
. If something is wrong with spring (1) and/or brake shoe (119), replace the brake shoe as an
assembly (plate (10) inclusive).