Clean the CS110 electrodes and/or insulators if any of the following conditions occur:
l
Insulators are dry and leakage current exceeds ± 4.2 nA as indicated by code 11.
l
Visual evidence of contamination (salt deposits, scaling, dust, spider webs etc.) on or
around electrode area.
l
Zero field reading with Zero Electric Field Cover exceeds 60 V/m.
Note: for good zero field readings, it is important that the inside of the zero field cover also
be clean.
How to clean the CS110 electrode head:
1. Remove the stator by loosening the two Phillips head screws on the motor assembly base
plate, allowing the stator to pivot and be removed.
2. Inspect the stator for any contaminant deposits and scrub such deposits off with soap and
hot water. Any residue may form nonconductive layers that can hold unwanted surface
charge. Using a brush that will fit between the shutter and the sense electrode, carefully
wash the shutter and sense electrode, along with the three insulators attaching the sense
electrode to the main body of the CS110. One brush ships with each CS110. Large offsets are
likely due to electrical charges residing insulative on deposits on metallic surfaces, while
large leakage currents are likely due to contaminated insulators.
3. Rinse well with deionized water and blow dry with air. Rubbing and wiping tends to induce
unwanted surface charging that will eventually dissipate.
4. Reassemble the stator, making sure it is positioned properly before tightening the two
Philips head stator screws. Avoid getting fingerprints, etc., on clean electrodes as they can
result in unwanted surface charge. (Clean cotton gloves are helpful.)
5. Attach the Zero Electric Field Cover to the stator and verify that the leakage current is < |0.5
nA| and that the zero field offset is < 60 V/m. Leakage current > |0.5 nA| and/or zero field
offsets > 60 V/m indicate problems with cleanliness and/or unwanted surface charge.
8.4 Checking ground integrity
The CS110 electric field meter needs to be electrically connected to earth ground for valid
measurements. For optimum operation, periodically check the integrity of this earth ground
connection by verifying that the resistance of the stator to grounding rod is <1 Ω.
CS110 Electric Field Meter 31
To Next Page
Loading...
