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People solving problems
“I used my Fluke 87V to
check the power, and that’s
when I found there was voltage bleeding to the ground wire due
to an improperly wired disconnect, electrifying the ground wire and the housing of the motor I was going to replace.”
Wind park
Working in a wind park doing trouble shooting can
be quite challenging sometimes. We installed a new meteorological tower with advance sensors up at
350 feet in the cold New-Brunswick mountains area.
We needed a crane platform that costs over $10,000
per day, not counting all of the ground support team.
We had some sensors that were not working correctly. We used the Fluke 289 true RMS multimeter to trouble- shoot. Using the Fluke 289, including the wire pares
and the low impedance and the diode check functions we were able to find damaged cables and bad sensors during the installation process rather than after (and having to reinstall equipment), saving a lot of time and money. As the new meterological tower is important to the operation of wind turbines that control icing mitiga- tion equipment and if not working or calibrated properly, it would affect millions of dollars in production costs. During the cold winter months, its calibration is critically important. If the calibration is off, it could impact the operation of the wind turbines and energy production. The data logging function of the Fluke 289 true RMS multimeter and the ability to push all of the trends were essential in the commissioning process and our ability
to verify proper instillation. The Fluke 289 permitted us to troubleshoot bad wiring, bad sensors and helped us in our commissioning report all in one compact instrument. Not forgetting also that it saved us tens of thousands of dollars in additional installation charges and millions of dollars in potential lost production.
Paper mill
Time is money in a paper mill so when a machine goes down the pressure is on to get it up and running as quickly as possible. I was called in one night when a motor controlled by a VFD kept tripping out and there were concerns we’d need to replace the motor. It’s a minimum of 8 hours to change this motor out and another two hours to get the machine back up and running.
Using my trusty Fluke 87 I was not only able to deter- mine that the motor was fine but that the real issue was a 5 V instrument supply module. These older drives have a very low tolerance for these modules and the Fluke was reading 4.77 Volts. The lowest possible voltage this drive can handle from the supply is 4.8 V. A $300 part and 15 minute change out had us back up and running in no time. Had it not been for the accuracy of the Fluke meter we probably would have changed the motor and still been stumbling around trying to find the problem. It’s a real testament to the accuracy of these meters and the trust we place in them every day.
I used my Fluke 87V to check the power, and that’s when I found there was voltage bleeding to the ground wire due to an improperly wired disconnect, electrifying the ground wire and the housing of the motor I was going to replace. n
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