Home Page

Installing high level float switch  -  Mystic Tan

The following procedures describe the installation of a high level float switch into the Mystic Tan sump pan. The purpose of the high level float is to prevent the rinse water solenoid from turning on when the float switch is activated by a higher than normal water level. The most frequent cause of high water levels in the sump is failure of  the sump pump to keep up with water introduced during rinse cycles. This typically being caused by a plugged strainer or internal pump valves.

The float switch itself is a similar device that is used to sense low fluid levels in both the DHA lotion and the sanitizing solution containers. Other than a small screwdriver, no special tools are required. The float switch is mounted into the sump pan with wires that lead up to the control box. Inside the control box, the switch leads are connected to appropriate locations to provide the required function.

Installation

First step is to turn off all power to the booth. Disconnect the ground plate wire within the garage. This is the green wire that comes from the ground plate within the booth, out of the sump through the white piping, and typically connects to a common ground connection just below the grey control box.

Inside the booth, lift the floor grating closest to the nozzles. Pull the ground wire back into the booth, being careful not to injure the end connector. It's a good idea to remove the 6" nipple from the garage side and help the connector through the piping.

With ground wire pulled back into the booth, you will now guide the wire through the coupling on the high level float switch.
	The float switch leads and the ground wire are now passed back through the nipple. The float switch coupling is then firmly pushed onto the nipple that passes through the sump wall.
This image shows the high level switch in place with the ground wire passing back through the coupling. feed all the slack grounding wire back through to the garage. The high level float can be adjusted by turning it slightly. Notice the height difference between the high level switch and the existing pump switch.
	Return the 6" nipple on the garage side of the piping

You can now reconnect the ground wire to the common ground terminal below the grey control box. Feed the wire so that it will not be exposed to injury by the nozzle assembly.

The two leads from the high level switch should be fed up to the left hand side of the grey control box. You will see a single green ground wire passing through a grommet in the left side of the control box. This is where you will pass the switch leads into the control box. 

	To assist in passing the switch leads through the grommet, carefully insert a small screwdriver through the grommet from the inside of the control box.  As you withdraw the screwdriver, follow with one of the switch leads. Repeat with the second lead so that both leads are passed through the grommet. Pull excess lead wire into the control box
This image shows lead wires passing into control box along side the single ground wire.

The float switch lead wires can now be hooked into the control circuitry. A quick explanation on the circuit and it's modification will assist in completing this part.

During a rinse cycle the PLC drives relay K3. This relay in turn provides the power which actuates the water valve solenoid. While K3 relay is driven, relay K4 which drives the sump pump is locked out preventing the sump pump from running. See sump circuit  for this arrangement. When we add the high level float switch into the circuit, it will remove the PLC signal from K3, which in turn removes power from the water solenoid. At the same time it releases the lockout condition of K4, allowing the sump pump to resume normal operation. This happens when the float switch senses higher than normal water levels. 

Connecting high level float switch

On the PLC, locate output port # 2. This is on the bottom section of the PLC. You will have to flip open the lower door to expose the terminals. Also locate relay K3, and specifically terminal 8 on the relay base. You will see a purple wire that connects both locations.

This image shows location of output port #2 , relay K3, and purple connecting wire. Notice that terminal #8 lies behind terminal #5 on relay K3. As a result, the wire on terminal #5 must be temporarily removed to gain access to terminal #8.

Remove the orange wire from terminal #5, relay  K3. This allows access to terminal #8. Remove the purple connecting wire from terminal #8, relay K3. Bring this wire forward and follow to the PLC outport #2. Remove  from output port #2. Withdraw the wire as it is not required in the modification. A second purple wire is connected to this port and should remain.

Connect one lead of the high level float switch to the PLC output port #2 and secure. Make sure the second purple wire is secured at this connection as well. Connect the second float switch lead to terminal #8 on relay K3. Reconnect the orange wire to terminal #5 on relay K3. Connections are now complete. Lay the switch leads along the wire harness and secure, allowing sufficient slack to prevent strain when opening/closing control box door. Close and secure control box door. Turn booth power on.

A review of the circuit modification in pictorial form;

Adjustments

The only adjustment available is had by angling the high level float switch within the sump. The float switch cuts out rinse cycles when active. The switch should be set high enough to allow normal rinse operation, but never so high that water is allowed to reach  the float switch coupling.  Excessive horizontal alignment may also cause the float to hang and create an error condition. Near vertical alignment should provide for normal sump operation, while guarding against excessive rinse water buildup.

To confirm operation, disable sump pump by disconnecting pump connector. Initiate a rinse cycle and allow it to run to completion. Observe the sump water level. It should be below the high level float coupling. Run a second rinse cycle and note if the cycle runs to completion or is cut short by actuation of the high level float. At some level, the high level float switch will disable further rinse cycling. At this point the sump water level should be below the float switch's coupling. Adjust as required. Reconnect the sump pump. 

- Note that this circuit modification electrically disconnects the water solenoid. It does not guard against mechanical failure of the water valve.

- Actuation of the high level float switch may also disable refilling of the Mystic meter. This may result in reduced lotion output if delivery of a tan is attempted during high sump level conditions. Simply running a rinse cycle once a high level condition is removed will allow normal operation.

Notice

The above information is for your consideration only. We recommend that any work performed be done by qualified persons. We will not be held responsible for the results of any work performed by way of consideration or implementation of the above information

© Copyright  SunlessSystems  2003