Emerson 2468CB, 2468CD manual 2-26, Indication

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

Indication	Fault(s)		Analysis and Corrective Action
State 3 (contd.)	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 short-
	alternates
		circuit to ground.
	between water and
	steam.	Check all even 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 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 even 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
	Internal circuit fault	If the wiring checks carried out as described above have
	on left hand circuit	not located a fault, then it is possible that an internal fault
	board or the	exists.
	display board	1.	Disconnect the electrode cable sockets from the
			input boards.
		2.	Make up four 10-way sockets (six or eight sockets
			required for systems with more than 16 points) with
			wire links connecting the following pins on each
			socket: 1-2, 4-5, 6-7, 9-10.
		3.	Insert these sockets in place of the electrode cable
			sockets in the input boards. The level display should
			now show an all steam state and no fault indication.
			If this does not occur an internal fault exists.
		The circuit fault may be on either input board or the
		display board. If spares are available, change the left
		hand input board first, and if the fault is not rectified
		change the display board followed by the right hand input
		board. If spares are not available, call the service
		engineer.
State 4	Internal circuit fault	This state is indicating a fault which is not related to an
Top half of fault	on left hand circuit	electrode error because no LED pairs are alternating
LED illuminated	board or the	between water and steam. It is therefore likely that an
No LED pairs	display board	internal fault exists.
		Follow same procedure as above.
alternating
between water
and steam
	Table 2.3 - Fault analysis/corrective action chart (continued)

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