Installing the Low Level Indicator (P/N or P/N )

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1 Instruction Sheet Installing the Low Level Indicator (P/N or P/N 276 4) 1. Introduction There are two Low Level indicator kits, one for flat bottomed tanks and one for the new finned tanks. P/N is for flat bottomed tanks; P/N is for finned tanks. The Low Level Indicator is designed for applications where the system melt rate does not exceed 11.0 lb/hr. At higher melt rates the Low Level Indicator will not operate properly. NOTE: This Low Level Indicator contains a mercury switch that may not be suitable for some applications where FDA approval is required (even though the switch is encased in solid plastic). Nordson offers an Optical Low Level Indicator (P/N ) that can be used in all applications.

2 2 Installing the Low Level Indicator 2. Description A Model 200 Applicator equipped with a Low Level Indicator displays a warning whenever the level of adhesive in the tank falls to the point that the unit should be refilled. The low-level light (the bottom light on the indicator panel of the applicator) comes on and stays on until the tank is refilled. The Low Level Indicator consists of a float, a counterweight, a lever rod, a mercury switch, and a light. The basic parts of the mechanism are shown in Figure 1. The float is balanced by the counterweight so that it rides half in the adhesive and half out. As the adhesive level drops, the lever rod to which the float is attached drops down and the mercury switch, which is attached to the pivot point, tilts forward. This action causes the mercury switch to close and turns on the light on the indicator panel Fig. 1 Basic Parts of the Low Level Indicator 1. Counterweight 2. Pivot point. Lever rod 4. Float

3 Installing the Low Level Indicator. Installation The following instructions are for customer installed kits. If the Low Level Indicator was ordered with the applicator, proceed to the Setup on page 8 of these instructions. NOTE: Remove the pump enclosure and remove the packing material that secures the float during shipment. If it is not removed before the applicator is put into operation, it might damage the pump. 1. Disconnect and lock out input power to the applicator. WARNING: Failure to disconnect external power to the applicator presents a serious shock hazard. The input terminal block and input terminals on the circuit breaker are still electrically energized if external power is not disconnected, even though the circuit breaker is open. 2. Shut off the air supply to the pump air regulator and disconnect the air supply line to the regulator.. Remove the electrical enclosure by loosening the captive screw on top. 4. Remove the pump enclosure by loosening the captive screw on top. 5. Remove the seven screws that secure the plastic tank enclosure to the tank. 6. Unplug the pump solenoid electrical plug from its receptacle and remove the pump by removing the three bolts and lockwashers that secure the pump to the tank. 7. Remove the plastic tank enclosure by pulling it straight up.

4 4 Installing the Low Level Indicator. Installation (contd.) 8. The Low Level Indicator kit for flat bottomed tanks includes a new tank cover but the one for finned tanks does not. If the kit has a new tank cover, remove the old tank cover and gasket and replace them with the ones in the kit. If the kit does not include a new tank cover, leave the old tank cover and gasket on the tank. 9. Find the wiring harness in the kit and route it (without making any connections) along the same path as the wiring to the solenoid valve. Place the indicator light near the notch for it on the circuit board and place the other end of the wiring harness on top of the tank cover Fig. 2 Two Possible Locations of J9 on Circuit Board with Digital Readout 1. J9 2. J7. Slot for low level warning light

5 Installing the Low Level Indicator 5. Installation (contd.) 10. Replace the tank enclosure, tucking the solenoid-valve wiring and the Low Level Indicator wiring harness underneath it. These wires should exit from the tank enclosure at the notch provided for them (see Figure 4). Do not install the enclosure with screws yet. NOTE: Make sure that there is enough wire pulled up from the electrical cabinet to reach the solenoid-valve electrical connector and the terminal block on top of the Low Level Indicator (see Figure 4) Fig. Installing the Low Level Indicator 1. Notch 2. Terminal block. Screw 4. Washer

6 6 Installing the Low Level Indicator. Installation (contd.) 11. Take the indicator light on the other end of the wiring harness and push it into the bottom slot on the circuit board. Secure it in place by wedging the rubber collar around the light into place. It may be helpful to use a screwdriver or similar tool Fig. 4 Mounting Low Level Indicator Light to Circuit Board (Top View of Board) 1. Indicator light 2. Circuit board. Rubber collar 12. Plug the female connector on the wiring harness into the three pronged male connector (labeled J9) on the main circuit board. The two possible locations of J9 are shown in Figure 2. NOTE: It may be helpful to obtain more working room by unplugging the two-part connector at J7. Be sure to hold the female connector while pulling on the male connector. Plug the connector at J7 back together once the connection at J9 has been made.

7 Installing the Low Level Indicator 7. Installation (contd.) 1. Replace the electrical enclosure and tighten the captive screw. 14. Some tank covers have a button plug, three screws, and lockwashers attached to them. The screws and lockwashers are shown in Figure 4. If these items are attached to the tank cover, remove them and save them for installation of the Low Level Indicator. If these items are not attached to the tank cover, proceed to the next step. NOTE: The button plug will be needed only if the tank is ever operated again without the Low Level Indicator on it. 15. Turn to the Setup on page 8 and decide if Method A or Method B is to be used. If Method A is chosen, proceed to step 16. If Method B is chosen, perform steps 2-4 in Method B and then return to these instructions and perform steps Take the Low Level Indicator from the kit and place the float mechanism through the hole provided for it in the tank cover (see Figure 4). 17. Install the Low Level Indicator on the tank cover with the three screws and lockwashers (which were either removed in step 14 or supplied in thekit)asshowninfigure4. NOTE: The float and lever arm must be snaked through the hole in the tank cover to get them through completely. 18. Attach the two push-on terminals on the wiring harness to the two prongs on the terminal block on the Low Level Indicator (see Figure 4). 19. Secure the tank enclosure in place with the seven screws removed earlier. 20. Remove the tank strainer from the tank and replace it with the one from the kit. 21. Replace the pump with the three screws removed earlier. Tighten screws to 20-2 N!m (15-17 ft!lbs) of torque. 22. Connect the plug on the solenoid wiring to its receptacle. 2. Connect the air supply line to the air regulator and turn the air supply to the regulator back on. 24. Proceed to the Setup Instructions, if using Method A.

8 8 Installing the Low Level Indicator 4. Setup Select one of the two methods of setting up the Low Level Indicator, Method A or Method B, depending upon how accurately the low level warning point needs to be set. Method A is the easiest to perform (about 10 minutes) but is the least accurate: the warning point may vary anywhere from 2 to inches from the bottom of the tank. Method B takes longer to perform (about 0 minutes) but allows the warning point to be set more accurately. The repeatability, once the warning point is set, will be the same for both methods. Method A The counterweight will be hot. Wear safety gloves and protective clothing to prevent injury. 1. Fill the unit with adhesive and begin normal operations according to the instructions in Section 4 of the Hot Melt System Technical Manual. 2. Open the tank cover when the low-level warning comes on indicating that the level of the adhesive in the tank is low, and observe where the float rides on the surface of the adhesive. Table 1 Method A - Adjusting the Counterweight Float Reference Groove Position Below the adhesive surface Above the adhesive surface Action 1. Remove the pump enclosure. 2. Loosen the locknut on the counterweight,. Turn the counterweight so that itmovesawayfromthepivot point of the lever rod until the reference groove is even with the surface. 4. Tighten the locknut against the counterweight. 5. Replace the pump enclosure. 1. Remove the pump enclosure. 2. Loosen the locknut on the counterweight,. Turn the counterweight so that it moves closer to the pivot point of the lever rod until the reference groove is even with the surface. 4. Tighten the locknut against the counterweight. 5. Replace the pump enclosure.

9 Installing the Low Level Indicator 9 Method A (contd.) Fig. 5 Setting Up the Low Level Indicator 1. Counterweight 4. Float 2. Pivot point 5. Reference groove. Lever rod 6. Adhesive level NOTE: If the adhesive is ever changed to one with a different specific gravity, the counterweight will have to be readjusted. The Low Level Indicator is ready for operation.

10 10 Installing the Low Level Indicator Method B WARNING: The metal parts of the mechanism, especially the float and lever rod, will be hot when first removed. Wear safety gloves and protective clothing to prevent injury from hot applicator parts. 1. Bring applicator to operating temperature so that the adhesive is in a molten state. 2. Remove the float mechanism from the tank by unscrewing the three screws which secure it to the tank, remove the two wires connected to the float mechanism with push-on terminals, and lift the mechanism out of the tank (see Figure 4).. Check the float mechanism for charring. If char has formed around the locking nut, remove it with a flameless electric heat gun before making adjustments. 4. Use the following chart and the illustration in Figure 6 to determine the correct position of the float on the lever rod. The x distance is the distance between the low level warning point and the bottom of the tank. The y distance is merely a convenient measurement for positioning the float. Table 2 Method B - Setting the Low Level Warning Point XDistance YDistance.00 inches 0.75 inch 2.75 inches 1.00 inch 2.50 inches 1.25 inches 2.25 inches 1.50 inches 2.00 inches 1.75 inches Forexample,ifthex distance is 2.5 inches (that is, the desired warning point is 2.5 inches from the bottom of the tank), the y distance should be 1.25 inches.

11 Installing the Low Level Indicator 11 Method B (contd.) WARNING: The counterweight will be hot. Wear safety and protective clothing to prevent injury Fig. 6 Method B - Float Adjustment for Warning Point 1. Y distance 2. Reference groove. Bottom of tank 4. X distance 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. Tighten the locking nut. 6. Place the float mechanism back in the tank, replace the three screws and lockwashers that secure it to the tank, and reconnect the wiring harness to the level-indicator terminal block as shown in Figure 4.

12 12 Installing the Low Level Indicator Method B (contd.) 7. Fill the unit with adhesive and begin normal operations according to the instructions in Section 4 of the Hot Melt System Technical Manual. When the level of adhesive in the tank falls to the point where the low-level warning comes on, open the tank cover and observe where the float rides on the surface of the adhesive. Table Method B - Adjusting the Counterweight Float Reference Groove Position Below the adhesive surface Above the adhesive surface Action 1. Remove the pump enclosure. 2. Loosen the locknut on the counterweight,. Turn the counterweight so that it moves away from the pivot point of the lever rod until the reference groove is even with the surface. 4. Tighten the locknut against the counterweight. 5. Replace the pump enclosure. 1. Remove the pump enclosure. 2. Loosen the locknut on the counterweight,. Turn the counterweight so that it moves closer to the pivot point of the lever rod until the reference groove is even with the surface. 4. Tighten the locknut against the counterweight. 5. Replace the pump enclosure. NOTE: If the adhesive is ever changed to one with a different specific gravity, the counterweight will have to be readjusted. The Low Level Indicator is ready for operation.

13 Installing the Low Level Indicator 1 5. Low Level Indicator Kit Parts List Part Description Quantity Note Low level Indicator Kit (Flat Bottomed Tanks) Low Level Indicator Kit (Finned Tanks) S Harness Assembly S S Lamp, Flying Lead, 18 V S Indicator Assembly S S Float S S Lever Rod S S Mercury Switch, w/leads 1 A S Tank Strainer (Flat Bottomed Tanks Only) S Tank Strainer (Finned Tanks Only) S Tank Cover (Flat Bottomed Tanks Only) S Lockwasher (Flat Bottomed Tanks Only) S Screw, Pan Head, M5 x 10 mm (Flat Bottomed Tanks Only) S Tank Gasket (Flat Bottomed Tanks Only) 1 NOTE A: The contact rating of the mercury switch is 0 VAC (extra-low voltage isolated class 11 circuits).

14 14 Installing the Low Level Indicator Original copyright date Nordson and the Nordson logo are registered trademarks of Nordson Corporation.

Series 3000V Low Level Indicator

Instruction Sheet P/N 237 473A Series 3000V Low Level Indicator 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