Emerson 2468CD 2-27, Indication, Faults, Analysis and Corrective Action, State, Bottom half of

Hydrastep 2468CB and 2468CD Manual 2468CB & 2468CD Dual Power Supply Version

Indication	Fault(s)	Analysis and Corrective Action
State 5	Electrode wiring or	Check that all odd numbered electrodes indicating
Bottom half of	internal fault	water have the correct pair of conductors connected.
		Check the connections to the right hand input board.
fault LED	Odd numbered
		Rectify wiring if incorrect.
illuminated	electrode
		Check ac voltage on all odd electrodes immersed in
One or more	connection open-
	circuit or	water with a true r.m.s. voltmeter. A voltage of less than
LED pairs
	short-circuit to	0.1V ac indicates a fault condition.
alternating
	earth	If wiring to all odd electrodes is correct and the
between water
and steam	Affected electrode	electrodes still give a voltage reading of greater than
	alternates	0.1V ac and a fault is still indicated, carry out the
	between water and	following procedure:
	steam.	1. Remove both conductors from electrode 1. With the
	Incorrect wiring,	conductors isolated from each other, the level
	broken connection	display should show electrode 1 as being
	or damaged cable	alternating between water and steam (green and
	assembly	red).
		2. With the conductors touching each other, the level
		display should show electrode 1 as being in steam.
		3. Repeat operations 1 and 2 for all affected odd
		numbered electrodes until a faulty indication is
		found.
		The above procedure checks the electrode wiring. If the
		display does not show the correct results, then check for
		a break in either of the suspect electrode conductors.
		Carry out repair to any faulty connection or substitute a
		new conductor or cable assembly in place of the
		defective item.
	Dirt on electrode	If the wiring checks carried out as described above have
	Affected electrode	not located a fault, then dirt on an electrode insulator
		may be the cause of the problem giving an effective
	alternates
		short-circuit to ground.
	between water and
	steam.	Check all odd numbered electrodes alternating between
		water and steam for dirt over the external insulator and
		clean with a cloth as required.
		Checking for dirt on the internal insulator of the
		electrode requires the draining of the water column
		(refer to the appropriate manual for the correct
		procedure).
		Once the water column is drained, check the ac voltage
		on each odd numbered electrode using a true r.m.s.
		voltmeter. Any electrode showing a voltage of less than
		3V ac needs cleaning or replacement. Electrodes must
		be removed from the column for inspection and
		cleaning.
		Note: The electrode insulator can be cleaned using a
		clean cloth

Table 2.3 - Fault analysis/corrective action chart (continued)

24685034 2-27