Hioki MR8880-20 User Experiences & Recommendations 1

[EngrOnTheMove]

Hello Generators & Motors group,

I'm looking in to getting an MR8880 to help with troubleshooting. So would like to get what your experiences have been and any learnings that can be shared.

1. Like application cases, successes or short-comings/limitations discovered from those, and recommendations in general.

2. Secondly, I'd like to know if you have used non-Hioki probes/cords with this or other HiCorder units (and the experience with them). This is because the Hioki ones recommended for this particular HiCorder are either exorbitant or in-terms of specs. not that accurate.

Looking forward to hearing from you all. Appreciate your experiences, recommendations, learnings, reviews, feedback...

Thanks!

 

[itsmoked]

I'm interested in this too. My old isolated channel Tek scope is needing a replacement.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[catserveng]

I recently picked one up used for a specific project, so far it has done what I needed it for, but it will be coming off that job fairly soon. I am looking at setting it up to replace my old chart recorder for doing standby generator and ATS testing, will add a logic probe for the digital inputs (such as Gen Start signal, Gen Brkr status, and ATS sources available and active source signals) and look at both utility and generator voltage and generator frequency. For now the 4 channel logic probe will likely meet all my current needs.

I have also wondered about their current probes, when I get it back in shop I will set it up with some of my various current probes, mainly from Fluke and AMEC and use a current source to see how well they work.

So far it has been a pretty durable and reliable unit, initially had some issues with the printer, but a good cleaning and reloading it with a new roll of paper resolved those problems.

Not sure of what kind of troubleshooting you're actually doing, so far I haven't found a single piece of test equipment that will meet all the needs I encounter. Some days a good quality DMM does the trick, other days a three phase power quality analyzer or a scope is needed, all depends on what you're chasing.

Hope that helps, will update once I have some info on the current probe capabilities.

MikeL.

 

[EngrOnTheMove]

Thanks for sharing @catserveng.

One of the immediate uses will be to troubleshoot a "failing" PT/VT on an online unit, by comparing the line-to-line voltages to the currents. Premise being that if the current does not dip in magnitude during a voltage dip event, then this would conclusively determine a metering issue instead of an actual fault condition. The AVR oscillates when these dips occur.

I've tried using a multimeter to "catch" an occurrence by comparing the secondary voltages of two PTs in the same system, but funny enough the dips do not occur for hours, on more than three attempts so far. So I'm thinking of resorting to using/getting a HiCorder to trigger on an occurrence.

When I look that Hioki probes specifically, the compatible current clamp probes have the following 3 issues:
1. More expensive than other manufacturer probes
2. Lower sensitivity than other comparable probes (surprisingly)
3. Low selection options for combined AC + DC probes

Ideally by investing in a HiCorder the intent is to have the capability to troubleshoot/measure a variety of circuits. The main ones being the 1A/5A CT secondary measurements (ideally with DC offset), the 120 Volt PT/VT secondary voltages, the control logic inputs for triggers & timing, and DC current measurement on process control like 4 - 20 mA input/output signals (transmitter, controllers).

I am still looking for a current probe (set) that would ideally do both AC & DC (Core & Hall effect integrated), that can do 1 mA to 10 A, which "doesn't break the bank".

 

[thermionic1]

catserveng

If I recall correctly, you have an Omicron relay test set. There is a software module (Enerlyzer) available that turns the unit into a 10 Ch (analog & / or digital) recorder / analyzer. They make current shunts so you can stab into current circuits (safely). Many times for me I've forgotten about this when I needed a scope or PAM or chart recorder. I keep an old junker laptop to run the SW if it's long term on site.

 

[catserveng]

To the OP, have you considered renting initially? At close to $4000 without probes at the start, if you're trying to figure something out short term maybe a rental device would be your best option, at least to start.

As for current probes, I'm looking at using the AEMC SL261 or Fluke 08i-110S for similar measurements as you are looking for.

thermionic1, yes I have a CMC353, a really nice set, but does not offer the ability to use as a recorder, when I was shopping for a test set, Omicron only offered that option (and it was pricey) on the CMC256 Plus (I believe now it also available on the CMC356). I have rented a Daneo 400 for more complex recording jobs, but like all Omicron products, they are VERY proud of it.

For a lot of the field recording jobs I get involved in, I'd rather use a smaller or more rugged unit, as most of the time they get left on fairly dirty and nasty sites for several days, sometimes weeks or months, depending on the ghost we are looking for.

MikeL.