I have four of these lifebuoy lights that stopped operating properly. The correct operation is that they are in standby when stored upside down. Unfortunately over time all of these units started to malfunction, I would find them turned on and operating when in storage mode.
I was a little annoyed as they were past their limited warranty period and had a $59.95 replacement value each. I don't know about you but $240 to replace the four lights wasn't some thing to be sneezed at. Overall the performance and operation was ok, it was just the shutdown function was no longer working.
I knew that I could get a spst tilt switch from the local electronics component shop for $3 each. I decided it wouldn't take much to modify the lights.
Tools and supplies:
Glass encapsulated 125V 3 amp AC.SPST, size 18mm(L) x 5.5mm (dia) Jaycar CAT NO SM1035
Soldering iron and solder (rosin core flux)
Heat shrink tubing and a hot gun or gas torch to shrink down the tube.
Clear acid free sealant
111 silicone compound (grease) for the o'ring seal at reassembly
Open the light, take out the battery and then carefully remove the lens from the plastic body.
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| Lens removed from the body of the light, take it off slowly and carefully |
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| Disconnect the red connector, and carefully remove the wire from the board. I used the solder iron and applied some solder to the end of the wire where it comes through the board, when the solder is liquid pull the wire clear of the board. Using this method the hole should be left clear. |
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| The red wire removed from the board, the tilt switch and shrink tube. |
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| Here I have bent the leg of the switch and doing a practice fit, once I was happy with the fit I removed the switch leg installed shrink tube and soldered it to the board. If the hole on the board wasn't open after removing the red wire, during reassembly the solder can be reheated and the leg of the switch inserted in to molten solder and a small amount of rosin core solder used to wet out the join. |
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| As can be seen there the switch with shrink tube has been soldered to the board, the second leg of the switch has been soldered to the red wire and the join insulated with shrink tube. To hold the glass tube of the switch in place I used acid free sealant, a cable tie was used to remove stress from the solder joints. The battery is inserted and the unit tested, if ok once the sealant is set reassemble the lense and give a final test. |
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| Lens attached and standing up right to test, battery installed. |
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| A few seconds later the unit is operational, then the big test by turning the light upside down, the new switch shut off power to the light. |
Mission accomplished, lights working and for $13 and an hour of my time, I saved what would have cost me over $240 to replace the lights.
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