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10.6.
Cleaning the Electrode in the Sensor Head
10.6.1.
Insulation Check of Anode
If the insulation resistance of the anode is not 10,000 M
Ω
or more,
the pressure indication is abnormal (the indication is higher than
actual or does not change), or the instrument may fail.
Insulation resistance of anode
You may receive electric shock if you touch it. Do not touch the
anode during insulation check.
Do not touch the sensor head.
Connect a insulation resistance tester to the anode pin and the peripoheral metal
portion as shown in Fig. 10-9 and conduct insulation check. If the insulation resistance
is 10,000 M
Ω
or more, there is no problem, but if it is less than 10,000 M
Ω
, replace the
anode with a new one.
If a insulation resistance tester is not available at hand, check insulation after
reassembly. (Refer to 6.)
Fig. 10-9 Insulation check of anode
10.6.2.
Cleaning the Anode
It can be a cause of leak. Also use care not to give a load to the
bottom of the glass portion when polishing the pin.
Do not polish the glass portion of the anode.
Check the A portion of the anode shown in Fig. 10-10 for surface condition.
If its color is metallic, the anode is satisfactory.
If the surface is discolored or stained, polish it with sandpaper. First, use coarse
sandpaper
＃
80 or #240 to polish it until the surface color becomes metallic and then
finish it with finer sandpaper of #400.
Before polishing
After polishing
Fig. 10-10 Anode
Insulation
Tester
＋
－
A portion
(electrode pin)
Glass
Summary of Contents for G-Tran BMR2
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