ChannelMag Section 4 Maintenance
4.6Transmitter Fault
4.7All Checks Good, But No Signal
4.8Erratic Signal
Should the resistances referenced above be correct, but the zero and span cannot be achieved, then the fault lies with the transmitter.
Check wiring in transmitter terminals in accordance with the transmitter instructions. Make sure there is actually flow through the channel.
Check the following:
a)Make sure the ChannelMag sensor is fully covered with media.
b)Check Paragraphs 4.1.4 to 4.1.6
c)Check if the ChannelMag sensor is correctly grounded (see Section 2.5)
d)Check for loose wiring.
e)Make sure cables are not too long. For multiple ChannelMag systems make sure electrode cables are separated from other cables (see Section 2.7)
f)The ChannelMag has high insensitivity to radios and variable frequency drives. If these are in close proximity to the transmitter or sensor then cable lengths should be kept to an absolute minimum.
4.9Signal Or Indication “Swing”
Check the following:
a)Make sure there is enough straight length of channel (see Section 2.3). If the requisite straight lengths are not available, then the “damping” in the transmitter must be maximized (see transmitter Instruction Manual).
b)Make sure there are no flow pipes or channels entering the channel in the location of the ChannelMag sensor .
c)Make sure there is no debris or loose cables in the vicinity of the electrodes.
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