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Transformer gas in oil analysis monitor/live data is this available?
3

Transformer gas in oil analysis monitor/live data is this available?

Transformer gas in oil analysis monitor/live data is this available?

(OP)
A salesman was telling me that the latest is a meter installed at a large oil filled transformer that will continually monitor for gasses in the oil. He said Qualitrol makes it. I called. They don't.  

Has anyone ever heard of or have experience with such a thing?
 

RE: Transformer gas in oil analysis monitor/live data is this available?

Several manufacturers: Hydran is one. There are several others that my ADD mind won't let me remember right now.  Try an internet search for transformer oil analyzers.

RE: Transformer gas in oil analysis monitor/live data is this available?

A few others I have used:

Morgan Schaffer - Calisto
Serveron (I wish I could remember the model)

You can even get the information online in real time from a remote location.  Dynamic Ratings comes to mind, but I'm sure there are other companies that do this.

Be mindful that most units simply monitor Hydrogen (and oftwen moisture) and they DO NOT REPLACE YOUR ANNUAL DGA!  There are several more advanced units that will monitor things like methane and acetylene.  I still would not consider these as a substiute for an annual DGA.  However the oil monitors can give you an early warning in case something is wrong with one of your transformers.

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If it is broken, fix it.  If it isn't broken, I'll soon fix that.

RE: Transformer gas in oil analysis monitor/live data is this available?

(OP)
Marmite

What is a carrier gas? And why is that better?

 

RE: Transformer gas in oil analysis monitor/live data is this available?

Bdn, the carrier gas is an inert gas such as helium used to transport the dissolved gases to the instrument. The downside is the maintenance liability, storage of replacement cylinders etc. That's why personally I favour the units that do not have any consumables.
Regards
Marmite

RE: Transformer gas in oil analysis monitor/live data is this available?

Do be aware that the expected lifetime of any of these units is significantly less that of the transformer they are mounted on.  Although some units are advertised as having no "consumables" they may still require service & replacement parts on a 3-4 year cycle.  

Purchasing a 10 year service contract for one of the monitors was quoted at 1.8 times the cost for the unit. The extra $4000 per year per monitor in O&M costs makes it hard to justify on all but our biggest transformers.

RE: Transformer gas in oil analysis monitor/live data is this available?

DGA on-line monitors are available with different levels of sophistication.Uppper band units have a separtae cubicle fitted to transformer sampling valves,with an integral oil pump to circulate oil and take sample ,say morning and evening, do DGA of all important gases and report results to an office 1000km away,all automatically.
Apart from Kelman some other sources.
1) www.weidmann-electrical.com
2) www.kjdyna.com
3) www.lgom.com.cn
The last ones are from Korea and China.

RE: Transformer gas in oil analysis monitor/live data is this available?

ABB make (used to make?) an online monitor. I think they were developing it with GE Syprotec. Perhaps another avenue to explore. Memory suggests it was called "T-Monitor" or something similar.
  

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If we learn from our mistakes I'm getting a great education!
 

RE: Transformer gas in oil analysis monitor/live data is this available?

T-Monitor was a comprehensive transformer on-line monitoring system.gases,temperature,moisture ,V,I etc.ABB also have an on-line DGA system.Kelman was taken over by GE Energy.

RE: Transformer gas in oil analysis monitor/live data is this available?

Thanks prc. We looked at that system many years ago for a generator transformer with a hot fault somewhere we couldn't identify in spite of several internal inspections.
  

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If we learn from our mistakes I'm getting a great education!
 

RE: Transformer gas in oil analysis monitor/live data is this available?

(OP)
I did get info from GE. Theirs monitors for 8 different gasses...And it can be ours, without installation costs for around $40,000. By the time its installed it will cost $100K.  I'm anticipating a tough sell.   

RE: Transformer gas in oil analysis monitor/live data is this available?

$40k and 100K installed!  Wow!  Now that's one expensive unit!  All you need is power and a set of alarm contacts!  Just a few years ago I was quoted $25K for an oil monitor for a critical GSU transformer.  We put a $9k unit on it.  It did Hydrogen and moisture only.  Last year it detected higher levels of hydrogen that had trended up for a few months so we took a DGA and found Acetylene so we took the unit offline a few weeks later.

In my experience, the units that detect Hydrogen only do a fair job of detecting a fault in time.  But like I said earlier, this doesn't replace the need for a DGA annually or even biannually.  You can go straight to Acetylene without seeing much Hydrogen in some cases.

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If it is broken, fix it.  If it isn't broken, I'll soon fix that.

RE: Transformer gas in oil analysis monitor/live data is this available?

(OP)
We're going to want this info online and available in the Control Room so its a little more than contacts and power.

Most of the time you can count on doubling the price of anything for install. Unions do cost, and in my opinion in in the trades anyway add a layer of required safety that is sometimes seems high but shows its value by not getting anyone hurt....

9K, I mean 18K is much more reasonable.  

RE: Transformer gas in oil analysis monitor/live data is this available?

Why is the info needed inside the control room?  Can't an operator go out and check it when an alarm is noticed?  My experience with operators is their first instinct is to ignore their indications anyway.  The real purpose of the oil monitors is not to determine what type of problem you have, but indicate that you may have an issue and should take an oil sample.  That's it.  Some plant engineers at the power plants would occasionally go outside and download the trend data from the monitors every once in a while, but for the most part it did little but give them peace of mind.

Out units were $9,000 to buy and cost about $4-5K to install.  We had the manufacturer connect them and set them up.  We had our union workers install the boxes and fittings on the transformers.   

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If it is broken, fix it.  If it isn't broken, I'll soon fix that.

RE: Transformer gas in oil analysis monitor/live data is this available?

(OP)
Turbine,

I thought the idea behind the gas in oil analysis is to see the trended data over a long period of time. The same thing for all the predictive maintenance gadgets we hope to install on the critical transformers. It's not just an alarming system at the transformer - that is the scenario we are hoping to eliminate.

In other words, the primary audience for this monitor will be the plant engineers and maintenance planners, not the operators. At least that is how I am conceptualizing this. If you have these installed at your plant...how do you use them?

RE: Transformer gas in oil analysis monitor/live data is this available?

Yes, the monitor trend data is the most useful thing about the devices.  It can show how rapid a fault is developing to give you some idea of your time frame before you must take your unit out of service.  Mind you that your DGA trend data does the exact same thing and monitors more indicating gasses.  The DGA is your true accurate monitor.

However, the online monitors usually store a year's worth of data in each unit.  Most units can be set up to alarm on absolute levels and trend data.  Thus, if you set your alarm levels properly, you can simply download the historic data in the event of an alarm.  The only thing on line monitoring does is eliminate somebody having to go outside and hook a laptop up to it.

The oil monitors real purpose is to tell you that it is time to take a DGA and determine if further investigation is necessary.  At this point when you see an alarm, you take an oil sample and download a year's worth of trend data and use it in your analysis.  The oil monitors are really an early warning system more than anything.  It tells you that you COULD have a problem and you SHOULD investigate it.  

I'm not telling you what you are planning to accomplish is incorrect.  On line monitoring is a nice feature.  However what I am saying is this level of installation might be unnecessary.  Remember that this was introduced to you by a salesman who's job is to tell you all the wonderful things the device can do.  This doesn't mean all of it should be used for every purpose.

What I'm suggesting is coming strictly from my experience first as an end user and now as a transformer manufacturer.  If you can add on line real time monitoring inexpensively, by all means do it.  But if it is going to increase the cost of the installation 3 fold, it may not be worth it.  Just food for thought.

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If it is broken, fix it.  If it isn't broken, I'll soon fix that.

RE: Transformer gas in oil analysis monitor/live data is this available?

(OP)
Turbine,

Thanks for the insight on how you actually use these.

I'm also gathering data into the world of computers servers...where I'm no expert either. But I was thinking the data from these monitors was to be stored on the server not on the device itself.

As another option I was hoping as they do with the relays that protect the transformers, see about locating the monitors inside the Control Room itself. The Control Room is between 100'-1000' away depending upon which transformer we're talking about.  

RE: Transformer gas in oil analysis monitor/live data is this available?

One model of  high end on-line monitors( the type I mentioned) was checked at site.The gas analysis given by this was counterchecked with lab analysis results.They were matching.But the cost of these complete gas analysers with remote monitoring facilty was prohibitive,and may justify only incase of large critical trfs like huge HV DC trfs ( each costing 5-10 MUSD) In other cases effective way may be simple manual monitoring hydrogen monitors ( like hydran )which can be monitored daily.In case of any abnormality, oil samples may be checked in lab at frequent intervals to assses the health and to take countermeasures.

RE: Transformer gas in oil analysis monitor/live data is this available?

The Hydran is a good unit.  It's fairly inexpensive and easy to install.  It's accuracy isn't great, though.  But it's close enough for a base loaded transformer.

My preference is the Morgan Schaffer Calisto 2.  It takes a 3 hour time average of the gasses in the oil and also heat it up to a consistent temperature so the readings are more accurate.  It's a bit more expensive and takes a bit more work to install (you need 2 free oil valves on your transformer), but it is easy to use and quite accurate.

The devices aren't instantaneous.  In fact, checking them once a week is plenty.  Just put an item on your operator's check list to write down the values on the unit.  The nice thing about the Calisto is you can move it several feet away from the transformer so it can be accessed without getting inside the transformer cage (if there is one).

prc hit the exact point I was making.  If you see an alarm on your oil monitor, you can take frequent oil samples which are very accurate and cost very little.  Now that you have a $100k estimate from the first vendor, you can look like a savvy engineer by having two installed for less than that and achieve the same goal by adding a little procedure.

If you can give me some historic DGA results, I can help you with where to set your alarms.

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If it is broken, fix it.  If it isn't broken, I'll soon fix that.

RE: Transformer gas in oil analysis monitor/live data is this available?

(OP)
Earlier today I met with the honchos and thanks to this forum I did have something to show. The Hydran unit was discounted because it appears at first glance to be moisture based, and apparently that is not the only problems they've experienced and would want something a little more robust.

And I was told that all of the transformers are as important as just the main ones. So the question was asked if one monitor could be used for multiple transformers? At some point I realize these are questions for vendors...

RE: Transformer gas in oil analysis monitor/live data is this available?

One transformer - one monitor.  Otherwise you won't have the trend data.  I would recommend looking into sme of the other monitors.  I have used the Calisto and found it works well.

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If it is broken, fix it.  If it isn't broken, I'll soon fix that.

RE: Transformer gas in oil analysis monitor/live data is this available?

bdn20004 Hydran and similar vintage instruments are not for moisture alone,it is mainly for detection of hydrogen the main fault gas in any major incipient fault.Yes if you want a portable gas analyser that is also available,using which you can check hydrogen content in other units also. Then the question of man hours for sampling and testing comes in to play.The argument all transformers are equally critical may be OK. But if the cost of monitoring equipment comes half the transformer price,investment justification will be difficult.Bosses may say, buy a spare transformer instead.

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