I have a cat with a keytroler scale that measures using hydrolic pressure. The problem is when the tilt is activated the forks drop. If you drive the forks also drop. Just started this after two plus years of proper service. You can power the scale off of a different power source and operation returns to normal. After contacting keytroler we moved all components outside the truck. No change noticed. My question is what kinds of problems have people had with electrical interferance or noise. How did you overcome the problem?
Showing items 1 - 19 of 19 results.
Removed scale and sent back to Keytroller. Gill took care of it and promptly sent it back. No more interference and a happy customer thanks to Gill. If you have problems with one he is the man to contact.
-job security-
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no way out
Just got put back on this lift with no way out. Got to love this.
proshadetree.... If the cable was cut while connected and the any of the wires touched the processor may now be damaged. A new cable/indicator may need to be installed.
Please call us to discuss this
Gill was very helpful in this matter. But before I got back to the truck a second mechanic removed the harness from the control unit and replaced it with a cut off serial cable. The unit now keeps the release solenoid energized. I kindly saw my way out of the loop as it is difficult enough to trouble shoot a single problem let alone one that was created by a different set of hands. Noise was suspected to be in control panel. That is where an am radio picked up static. Not a highly scientific way to locate it but at the suggestion of a fellow tech.
Keytroller has been selling and servicing the Vanguard weighing system for more than 5 years. The system itself is galvanicly isolated against noise.
There have been certain trucks that require further isolation. These are typically AC powered trucks. Keytroller has a non-conductive fitting that further isolates the solenoid, transmitter and the transducer.
In most cases this corrects the issue.
The only explanation I have for the new behavior after 2 years of UN-eventful service is possibly some electrical part wearing beyond tolerance.
Such as a drive motor or other electrical part that has worn brushes. The brushes are chattering and emitting more electrical noise than normal.
The Vanguard suddenly picking up this noise through cabling or hydraulic hose and transmitting it though the bypass module and causing the solenoid to energize.
We have worked with this dealer/customer on this issue, and have recommend the non-conductive fitting as described above.
I would also suggest that while the battery is out, to clean ALL the corrosion where the cables run under the battery, and give a good eyeball to where the cables run towards the front of the battery under the weldiment. the cut on that part of the battery box is sharp enough to eventually wear a cut through the power cables. just replace any cable that looks like the insulation has been sitting in the corrosion or is cracked from rubbing.
Imnsho EMI in forklifts also is just about as likely to be from induced current, static discharge and/or counter EMF as it is from 'ground loop' (feedback).
I worked 6 years in electro magnetic interference (EMI) suppression on military aircraft. Most of the issues that were encountered, (things turning on when they should not, or irratic componet behavior) were either a ground loop problem, or an emission from a radiated source.
As previously suggested, check chassis ground from battery for resistance, remove the battery and run the truck, try taking a fused wire and temporarily grounding componet return to chassis. Attemp to isolate the issue and see what you come up w/.
only a few suggestions to try.
There was problem with transduser on lifting presure on some earlyer models of diesel forklift that cause forks to dropp. There have alse bine mutch problem with joystick try to switch with the attachment.
Bjarte
Post at 2talservice.no
Is the truck frame clean? Voltage on the frame can cause all sorts of odd and expensive failures. Do you have service information on the scale and can you send it to me specifically a schematic. In addition, send me the complete model and serial number.
ltrm812 at gmail dot com
This scale has a return hose that goes from a metering block back to the tank. It taps into the main pressure line. The lowering valve on the block receives 9 volts when tilting or side shifting or traveling. All input wires have been checked to see which change when unit is malfunctioning. None were found. It could be a bleed between two that have not been tested yet. I have not sourced a filter yet. I will try one when i can get back to shop.
LTRM,
when motor runs and valve is not activated it sends oil back to tank generally
Dumb question, those EP18 cats have manual hydraulic control valve, where is the oil going?
Something else for you to consider, have you ever seen non conductive hoses before? They are normally orange in color. I usually see them around flow sensors. You probaly have a pressure transducer but if you have nothing else to try...
check here, they have dc/dc converters and line filters also, just do a search for 'filter' and it will show you those
ht tp://w ww.translectricinc.com/default.aspx
just remove the spaces from the url
It is a vanguard scale from keytroler. It taps into the main lift hose. Power has been relocated twice. Have been in touch with keytroler twice. Shielded cabels are in use throughout. I have seen no mention of a filter in the instructions or on their web page. Any recommendation on a particular type?
sounds like its picking up noise from the pulsing from the traction and pump motors but i dont see how the keytroller could make the truck lower, all it does is turn the truck on and off and monitor impacts if it has that option installed.
Have you tried relocating the connections where its connected to it's power sources? Also what stam suggested is usually imperative when installing shockwatches or keytroller devices, they even usually recommend it. An inline power filter should eliminate any noise the system generates and translate the 'dirty power' from the battery into a stable energy flow.
One other thing is check where the cables are ran, if they are near any motors you will probably have to re-run the cables away from any motors or use shielded cable or something.
just some thoughts about this strange issue ;o)
Truck has a static strap. Noise is located in the control panel. Tilt,side shift, or any drive motion will cause the forks to lower. Steer has no effect on unit. Keytroler suggested shortening all leads and moving inverter out of truck, like on hood or dash panel. Had a small effect, it actually made it worse. I was told that an AM radio will pick up noise and help to zero in on it. Anyone ever try such a thing?
A line filter or voltage filter is usually used to help remove electrical noise and feedback into the truck. I have never had to use one on a 12 volt system usually only on electric forklifts for rf terminals or other accessories. Maybe it is what you need? Strange that worked fine for 2 years, maybe a diode has gone bad somewhere. Sorry i could not be of more help to you. Does the truck have a static strap if so maybe it isn't conducting to the floor anymore?
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