Low Level Indicator. Part E, Section 1. This section covers the following unit configurations. 3500V 3700V 3800V 3900V E2EN 03 [3V LLI] 4

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1 Part E, Section 1 This section covers the following unit configurations. Model 3400V 3500V 3700V 3800V 3900V Voltage All Pump All Manifold All Control All

2 E 1-0

3 E 1-1 Section E 1 WARNING: Allow only qualified personnel to perform the following tasks. Observe and follow the safety instructions in this document and all other related documentation. 1. Introduction The low level indicator sends a signal to an external device when the adhesive level in the applicator s tank is low. The external device can be a Nordson vacuum hopper feeder that automatically adds more adhesive, or a customer-supplied light that warns operators when the adhesive level is low. The low level indicator consists of a float, counterweight, lever rod, mercury switch and terminal block. The float is balanced by the counterweight to ride half in and half out of the hot melt material. As the adhesive level drops, the float attached to the lever rod drops down. The mercury switch attached to the lever rod tilts forward. This action causes the mercury switch to close and activates the terminal block. The indicator is intended for 30 VAC maximum, Class 2 circuit operation as defined in Article 725 of the National Electrical Code.

4 E Installation WARNING: Hot! Risk of burns. Wear heat-protective clothing, safety goggles, and heat-protective gloves. Hot melt material may be released forcefully. 1. Drain the tank of all hot melt material. WARNING: The applicator contains energized electrical components with potentials that could be fatal. Disconnect and lock out input electrical power to the unit before proceeding further. Only qualified personnel should install and operate this equipment. 2. Remove the pump enclosure. 3. Remove the electrical enclosure and rear cover from the unit. 4. Remove the screws holding the pump pan to the tank cover. 5. Knock out the lever rod opening on the tank cover.

5 E Installation(contd.) Fig. E Indicator assembly 2. Float 3. Tank barrier 4. Center frame 5. Wires to customer-supplied remote device 6. Wires to 7. Terminal block 8. Counterweight

6 E Installation(contd.) 6. Clean the tank of any debris before filling with fresh hot melt material. 7. Remove the float from the lever rod and slide the lever rod through the opening in the pump pan. 8. Mount the indicator to the pump pan and secure with the screws removed in step Attach the float to the lever rod. The mercury switch activates when the lever rod drops below horizontal. 10. Loosen the locking nut above the float and screw the float up or down the lever rod to the position that will produce the desired low level warning point. NOTE: The X distance in Figure E 1-2 is the distance between the low level warning point (reference groove) and the top of the tank strainer. The recommended X distance is 63mm (2.50 in). Recommended Y distance is 36mm (1.41 in). 11. Tighten the locking nut when the float is at the desired position. 12. Place the tank barrier in position around the float. 13. Fasten the terminal block bracket to the center frame. Fig. E Secure the terminal block to the bracket.

7 E Connect the indicator wires to the porcelain connector on the indicator. 16. Route the wires behind the tank and through the recess in the center frame, then bring them up to the terminal block. 17. Connect the indicator wire ends to the terminal block. 1 2 Fig. E 1-3 Connecting wires to the terminal block 1. Wires to low level indicator 2. Wires to customer-supplied remote device The low level indicator can now be connected to a remote device provided by the customer. Connect the wires from the remote device to the terminal block directly across from the wires to the low level indicator. 19. Replace the electrical enclosure and the front cover. Replace the pump enclosure and tighten the locking screw.

8 E Setup WARNING: Hot! Risk of burns. Wear heat-protective clothing, safety goggles, and heat-protective gloves. CAUTION: Remove the retaining rubberband from the float assembly before proceeding to prevent the melted rubberband from falling into the tank. 1. Fill the applicator with hot melt material and begin operation according to the Operation section of the manual. 2. When the low level warning indicator comes on, open the tank cover and remove the tank barrier. 3. Observe where the float rides on the surface of the hot melt material. 4. If the reference groove is below the adhesive surface, remove the pump enclosure, loosen the locknut on the counterweight and turn the counterweight so that it moves away from the pivot point of the lever rod. Continue turning the counterweight until the groove floats at the surface. ADHESIVE LEVEL 5. If the reference groove is above the surface, turn the counterweight so that it moves closer to the pivot point of the lever rod. Continue turning the counterweight until the groove floats at the surface. NOTE: If the hot melt material is changed to one with a different specific gravity, readjust the counterweight Fig. E 1-4 Float Reference Groove 6. Tighten the locknut against the counterweight. 7. To adjust the low level warning time, re-position the float up or down on the lever rod. NOTE: Tank capacity must be at least 50% when the mercury switch activates. 8. Replace the pump enclosure. The low level indicator is ready for operation.

9 E Parts List Part Description Quantity Note ÁÁ Service kit, Level Indicator ÁÁ Level assembly indicator Á 1 A ÁÁ Tank barrier 1 ÁÁ Washer, flat, x x inch ÁÁ Screw, Hi Lo, Pan Hd, Rec, 2-18 x 1.00 inch Á ÁÁ 4 station marker strip Á ÁÁ Terminal block bracket Á ÁÁ 4 station terminal control block Á 1 ÁÁ Screw, Pan Hd, Slt, M3 x 16 mm ÁÁ Wire group 1 Á NOTE A: The level assembly indicator includes a mercury switch (P/N ).

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