Hoffman Media EDD-4C manual Connection box-power and control lines, 24VAC/DC S.B. Pre-lube

Caution:	External 24 VAC power source must be
	isolated from ground.

2.Route the power cable through a cable strain relief on the left side of the connection box (Figure 4).

3.Connect the green ground wire to a chassis screw or bolt, preferably using a ring terminal. See Figure 4.

4.Route the control cable through the right cable strain relief (Figure 4).

5.Connect control cable according to Table 1.

The connection box power and control line descriptions are shown below.

Table 1: Connection box—power and control lines

Cable or Terminal (Figure 5)	LED	Function
	indicator
	(Figure 6)
Power Cable (contains 3, 18 AWG		This cable provides power to the Dripmaster. Using the
wires)		selector switch and appropriate terminal block, for line power
		(115 VAC or 220 VAC) or 24 V AC/DC can be supplied.
Control Cable (contains 8, 22 AWG		Input and output control or status signals are routed through
wires):		this cable.
24VAC/DC S.B. – Pre-lube	SB	When applying 24 V AC/DC to these terminals, the
mode		Dripmaster switches to the Pre-lube (pump off) mode. The
		Dripmaster rate is 2 dpm in this mode. The SB LED (item 3
		in Figure 6 also lights. See page 13).
LL – Total lack of oil	OIL	A dry contact that closes when a total lack of oil condition
		occurs. The OIL LED (item 1 in Figure 6) also lights. See
		page 13.
PULSE – Drip indication	DRIP	A dry contact that transmits the drip rate. The contact closes
		for every drop fed to the line-shaft. The DRIP LED lights
		momentarily whenever an oil drop passes through the
		Dripmaster.
O.K. – Sufficient lubrication1	OK	A dry contact that closes when sufficient oil is present. This
		contact closes when the OK LED (item 2) in Figure 6 lights.
		See page 13.

1In the Pre-lube (pump off) mode, the OK contacts are always closed.

During the transition period from the 2 dpm Pre-lube mode to the preset Normal (pump on) drip rate settting (20 to 40 dpm), the OK relay is not energized (contacts open and OK LED is off) since the 15 dpm threshold has not yet been reached. In order to signal to the SCADA room that the Dripmaster is functioning normally during this transition period (from 2 dpm to the preset value), the OK contacts of the external time delay relay should remain closed for approximately four minutes. In case of a total lack of oil (e.g., empty oil tank) the LL contacts close, and the OIL LED turns on.

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