Graco Pneumatic Electric Lube Sentry Valve User Manual

Pneumatic/Electric Lube Sentry Valve

PNEUMATIC LUBE SENTRY VALVE

OPERATION: Initiate lubricant ﬂow from the lube pump serving the

divider valve or pump to point system (until ﬂow has been established, the electric or pneumatic circuit to the Lube Sentry must be bypassed). Lubricant passing through the hydraulic section of the valve (See Figure 1 or 2) from port (1) to port (2) moves to piston (3) in the direction of the arrow. The actuator rod (4) is attached to piston (3) and simultaneously moves in the same direction allowing the directional spool (5) in the air valve of the Pneumatic Lube Sentry (See Figure 1) to permit air to ﬂow between port “A” and port “C” or tripping the microswitch(es). (See Figure 2 Note 2 on the Electric Lube Sentry.) The Lube Sentry is now in a ﬂow position.

When lubricant ﬂow stops, spring (6) returns piston (3) in the opposite direction, closing the porting to the lube outlet (7). The lubricant ahead of piston (3) is forced back through the adjustable needle valve (8) at a controlled rate. As piston (3) returns to the right, the attached actuator rod (4) moves the Pneumatic Lube Sentry directional spool (5) permitting air to now ﬂow between port “A” and port “B” (See Figure 1), or changing the position of the microswitch(es) (See Figure 2 Note 2) on the Electric Lube Sentry. The Lube Sentry is now in a no-ﬂow condition. Figure 1 shows a typical no-ﬂow position.

Adjusting needle valve (8) clockwise increases shutdown time. A counterclockwise adjustment decreases the shutdown time.

Note 1: Pneumatic Valve Operation (During Lubricant Flow)

ELECTRIC LUBE SENTRY VALVE

Flow - Green Light - ON; Red Light - OFF

No-Flow - Red Light - ON; Green Light - OFF

Operation Port “A” Port “B” Port “C”

Norm. Open Air In Plugged Air Out

Norm. Closed Air Out Air In Plugged

Figure 1. Pneumatic Lube Sentry Valve Figure 2. Electric Lube Sentry Valve

Note 2:

FLOW CONDITION :

For Closed Contact: Use Red and Blue Wires (Red Common) For Open Contact: Use Red and White Wires (Red Common)

NO-FLOW CONDITION: For Open Contact: Use Red and Blue Wires (Red Common) For Closed Contact: Use Red and White Wires (Red Common)

CAUTION: If only two of the three wires are used, tape un-used wire.

Manzel® Pneumatic/Electric Lube Sentry Valve

INSTALLATION

General Lube Line Connection

The Lube Sentry Valve should be located in the lube line 1. downstream of pump, ﬁlters, and controls, but ahead of the master divider valve. (A high-pressure line ﬁlter placed after the pump is insurance against system plugging due to oil-born dirt.)

A pressure rupture assembly (Disk Relief Type) must be located 2. in the main lube line between the pump and the line ﬁlter.

Always install Lube Sentry with “LUBE OUT” port up, to permit 3. natural air purging of the device.

General Shutdown Reaction Adjustment

See graphs for minimum ﬂow rates, with various viscosity oils, 1. and shutdown time recommendations.

Start with the adjustment screw (Figures 1 & 2, Item 8) 2. ﬂush with end of housing. Turn on lube system with pump discharging oil at normal ﬂow rate and pressure.

45425

NOTE: Do not use below minimum recommended

ﬂow rates or inconsistent shutdown times occur.

Graph 1. Minimum Flow Rate

Slowly rotate adjustment screw clockwise until the electric 3. switch/air valve changes mode (ﬂow condition).

Stop oil ﬂow and note time for electric switch air valve to 4. change mode (no-ﬂow condition).

Start normal ﬂow of oil and note that the electric switch/air 5. valve changes mode (ﬂow condition) within two minutes and remains in this mode as long as normal oil ﬂow continues.

For positive shutdown indication on the Electric Lube Sentry, 6. an ohmmeter or continuity meter should be connected to wiring as follows: No ﬂow condition – continuity between red and white wires. Flow condition – continuity between red and blue wires. Caution – In an explosive atmosphere, use only approved device for checking continuity

This is the minimum shutdown time attainable for the 7. application. The shutdown time can be increased by continuing to turn the adjustment screw clockwise. Caution – Do not adjust shutdown time greater than shown on graphs or inconsistent shutdown time will result.

Pneumatic Lube Sentry Valve Installation

Pneumatic Connections

Series Type (in-line) Safety Control Pneumatic CircuitsA. (See

Figure 3)

Trace pneumatic safety circuits from the source of its take-off 1. air supply through the various safety devices used on the engine and compressor to the entrance of the pilot air port (bonnet port) on the safety control valve or gas shut-off valve.

Select the most convenient location to break into the air circuit, 2. either between two other safety devices or between the last safety device and the bonnet port of the safety control valve.

NOTE: At minimum ﬂow rate, the shutdown time is not adjustable. Times indicated are approximate results when the attached procedure is followed. Attempting to increase the shutdown time will result in inconsistent shutdown time.

Graph 2. Minimum Shutdown Time

Break the air circuit at the selected point and tube the Lube 3. Sentry Valve into the circuit with air ﬂow entering port “A” and leaving port “C” (See Figure 1). If gas is used as the control medium rather than air, tube the exhaust port “B” into a suitable vent line.

CAUTION – Never plug port in series type shutdown circuits.

To test device for operation, start engine to initiate ﬂow in the 4. divider valve system. Operation of the air valve within the Lube Sentry will be observed as the tripping out of the reset latch (manual override) lever on the safety control valve (see Figure

3), and the continued operation of the engine.

After a short interval of running during which the engine and compressor receive sufﬁcient lubrication and all other safety devices move to the RUN position, dump the output of the pumps serving the divider valve systems by removing the pump blowout disc or a pipe plug from the pump manifold assembly. When the ﬂow to the distribution system stops, the Lube Sentry should operate to dump the pressure in the pneumatic safety circuit, dropping out the safety control valve to stop the engine. (If shutdown action is sluggish, reduce the setting of the adjustable oriﬁce through which air for the safety circuit passes.

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