Topcon Measuring Tools & Sensors - Recent Questions, Troubleshooting & Support

Hello, have you already fixed it?

Topcon Cl- 100... | Answered on Jan 19, 2019

There are 2 small screws holding the rotating head motor in place. Likely you just need to loosen these screws, and adjust the motor position and retighten.

Topcon Measuring... | Answered on Nov 02, 2018

Hola, ya lo has solucionado?

Topcon Cl- 100... | Answered on May 30, 2017

taken from Pauldos Personal Laser Blog,
The Topcon RL-50B and RL-60B leveling lasers use a fairly unique compensator arrangement. Most leveling lasers use a suspended compensator arrangement, with a lens or mirror on the pendulum. The pendulum is usually metallic, and inside another metallic barrel, so that an electrical connection between the pendulum and outer barrel indicates to the electronics that the compensator is 'out of range'. The RL-50B/60B has a fluid compensator system where the laser beam is reflected off an interface between the fluid and a window, with the level of the fluid influencing the reflection angle of the laser beam. Because there is no electrical aspect to the compensator, an optical system is used to detect when the compensator is 'out of range'. In the output structure of the laser, a glass window at forty-five degrees is used to reflect a small portion of the beam to a photo detector. When the laser is level, the small portion of laser beam strikes the photo detector.

A common fault with these lasers is to constantly indicate 'out of level'. This occurs when there is insufficient beam intensity on the photo detector. The standard solution for this fault is to clean the 45 degree window. Sometimes, this does not bring the laser back to life. I have stripped down a couple of these lasers to try and figure out what is going on.
At first, I thought that maybe the laser diode could be down on power, reducing the available beam, but I quickly discounted that, because the laser diode output is feedback controlled, so the output power is stable up until the point of complete failure. One of the units I disassembled had cracks in the compensator housing, and the fluid level was low. I don't know whether the fluid leaked or evaporated, but in either case, there was no way the compensator could be repaired. In another unit, I noticed that the fluid was discoloured. Since I don't know what the composition of the fluid is, I don't know what could cause it to discolor. Perhaps extremes of heat or cold may damage the fluid. If the fluid is discolored, that may reduce the available laser power at the output. The question is, can we compensate for this? (pun not intended)

I decided to reverse-engineer the photo diode circuit, and see if there was any way to improve it. There is. The photo detector amplifier is a standard op-amp inverting amplifier. The feedback resistor, surface mount R23, is 470K. I changed this resistor to 680K to increase the gain of the amplifier, and bingo! the laser works like a real one again. Extensive testing in the workshop and in the field shows that the laser functions as originally designed in all ways. I have done this modification to over fifty of these lasers now, and the modification extends the life of the laser anywhere from a few months to a few years, with the average about one and a half to two years. Customers are always happy to not have to buy a new laser for another year or so, so this modification is always embraced when offered. I have never figured out what is going on with the fluid, but since I have a solution (again, pun not intended), I don't care.

cleaning instructions :
Remove the housing. Remove the battery holder. Loosen two small silver grub screws on the turret. Lift turret off. Clean slant window with acetone and a cotton bud. Avoid smearing the glue in the corners over the window. Flatten and curve a cotton bud to clean the inside of the slant window. Clean the folding mirror under the slant window. Replace the turret. Turret has a small amount of play, so align it for best operation before tightening grub screws. Re-fit battery holder and housing. All done!

Topcon Rlh3c... | Answered on Jun 27, 2016

Tengo el mismo problema. Encontr? la

Topcon Gts-601 /... | Answered on Mar 11, 2016

you will need to contact topcon this is a very bespoke item and its unlikley other drivers or sync tools will work and the link software may need to be licensed

Topcon GTS-102N... | Answered on Nov 07, 2015

Either the laser diode has failed, or the main circuit board is not activating the laser. Either way it's an expensive repair, and it will have to go to a service shop to get looked at. I recommend finding a shop that gives free estimate, as you may not want to proceed with the repair.

Topcon Rlh3c... | Answered on Sep 07, 2015

Sound like the laser diode is failing. It's power is likely just strong enough to get the level position right, then dims as it runs. The unit, no longer seeing the laser, decides it's out of level and stops. Or the oil in the compensator is leaking, and the same process is happening. Unfortunately the replacement part is not economical to replace.

Topcon Rlh3a... | Answered on Sep 07, 2015

This is not a battery problem. It likely levels to the back corner, then to the front corner then roughly back to the middle and spins at about 150 rpm and the lights on the front blink.

There are a couple things that can cause this. the most common is the the compensator cant find the laser. 5 screws hold the main housing on to the base. Remove the housing and inspect. if the internals are coated in oil, then the unit is done. The replacement part is too expensive.
If the inside is dry, there is a small circuit board on the left side of the metal compensator frame. Resolder the pins in the board, and the connector going to the side board, located on the main board. about 30% of the time, this will get the laser running again. If not, the laser diode is likely dead, and it's not repairable.

Topcon Rlh3a... | Answered on Sep 07, 2015

Only tech's at topcon shops (or former techs) have thoes, and are usually unwilling to share. It's not like a car, where aftermarket people make manuals and sell them.
If you tell me what you need, i may be able to help you. While i no longer have the manual, I've worked on literally hundreds of them.

Topcon Rlh3c... | Answered on Sep 06, 2015

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