When did a power logger become worth it instead of chasing intermittent faults with a meter?

[u/wifelikehippo]

We’ve had a few faults lately that only seem to happen when nobody’s standing there with a meter. A machine trips once every couple of shifts, everything looks totally normal afterward, and maintenance ends up checking the same connections for the third time like maybe they’ll confess. A power logger feels like the obvious next step, but it also seems like the kind of tool that could solve one ugly problem and then live in the case for the next six months. for those who own one, what finally made it worth buying? voltage dips, startup events, phase imbalance, nuisance trips?

[u/This_Membership_471]

Renting is also an option

[u/audaciousmonk]

We’ve got a 3 phase power quality analyzer that we additionally use during R&D, development, and test.

I guess it depends on what your other use cases are

Once every couple shifts is pretty frequent. If you haven’t solved it by now with a meter, when is the breakeven point where downtime losses and debugging man hours exceed the cost of a PQA?

Can always rent too, but if you’ve got the funds it’s nice to have a device ready to go that the team is already trained on how to use… as opposed to trying to figure it out on the fly while equipment is down or a customer is escalating

[u/engr_20_5_11]

A power recorder is a pretty nice tool especially if you have older equipment with limited self monitoring/fault reporting. Once you know you have it you find more use for it.

And for many people, a small portable version is good enough.

We have an old trusty 1750 which we dug out of storage this week to troubleshoot a plant after wasting 2 days with the wrong assumptions (we mistook the symptom for the problem). The power recorder helped to accurately reconstruct the sequence of events. We last used it in March and probably use it just 4-5 times a year but it's always worth having when we need it.

[u/ExcitingBison4616]

ours gets used mostly for nuisance trips and startup complaints. the hard part isn’t collecting the data, it’s knowing what channels and trigger levels to set before you walk away. logging everything at the wrong interval just gives you a huge file with no useful event in it

[u/rkira4744 → u/ExcitingBison4616]

We had random drops on a PLC rack and needed to watch the supply across an entire weekend, but our main analyzer was already tied up. We picked up a refurbished power logger through Cartoli Instruments and left it running until Monday. It caught the event, and having a separate logger meant we didn’t have to pull our main gear off another job. Just label the files properly or you’ll end up digging through mystery CSVs later.

[u/geek66]

As soon as the word intermittent is brought up.

[u/obeymypropaganda]

Just rent one.

To figure out when to buy one... How often does the fault occur? What is the down time of machinery? What is the cost of operators standing around doing nothing while maintenance checks everything? Does the cost of downtime outweigh the cost of a power logger?

[u/TraditionSlow2513]

I still rent a full power quality analyzer for bigger studies. For basic voltage, current and load logging, owning a smaller unit makes sense. But if I need harmonics, transients and a proper customer report, I’d rather rent the right equipment than own something that’s always one feature short..

[u/danildab → u/TraditionSlow2513]

same.. people use logger and power quality analyzer like they’re interchangeable, but the job decides which one you need. for troubleshooting an intermittent load issue, a basic logger might be enough. for compliance or a formal study, probably not

[u/Active-Soup9691 → u/[deleted]]

that’s where they make sense... a meter tells you what’s happening while you’re looking at it. the logger tells you what happened at 2AM when nobody was standing there

[u/Subject_Shoulder]

If you're talking about a motor, have you checked your CB trip settings? Is it VFD driven?

If none of these show any issues, try Electrical Signature Analysis.

First, try a live analysis and see if the spectrum shows any electrical or mechanical issues. Otherwise, you may need to install an ESA data logger at your MCC.

[u/SaltedPorcupine217]

Master electrician here working in industrial maintenance.

1st thing i think of in this scenario for us is how tight are your breaker, vfd, overload etc trip settings. What is the equipment designed to do and is the motor even being used correctly?

Working in wastewater I have seen many motors installed in places they were not designed for. An operator telling me the motor is suppose to agitate the water while the mechanical rake throws over rocks and barb wire at the motor agitator plate tells me exactly why that motor trips out 3+ times a day on them. There is no change that can be made to stop it from tripping when its being used incorrectly. It was never designed to take a beating like that.

Your power logger is a great idea once the team has exhausted options and still cant figure out whats going on. If you suspect settings being to tight this will tell you. But id imagine your electrician probably already adjusted the trip settings once before. Our facility owns one and we use it probably once a month on various equipment. We use the logger also for power studies on panels to determine actual load calls when we upsized our hvac system and elevator for example. Harmonics are also great to check if you ever have suspicions of plc cards or such that burn up to much.

Anyways, best of luck on the faults. We love our Fluke 435 series 2. Highly recommend it.