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60 Hz to 50 Hz Converter 1
- Thread starter sunrays
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If you haven't already, it might be worth double-checking to see if your 50Hz equipment might actually run just fine on 60Hz. Typically, transformers will tend to run hotter on lower frequencies - so running 60Hz equipment on 50Hz can be a heat issue for marginal designs. But the other way around (going to a higher frequency) is often no problem.
By way of example, equipment rated for 50/60Hz power will sometimes (often?) work just fine on 400Hz aircraft AC power.
By way of example, equipment rated for 50/60Hz power will sometimes (often?) work just fine on 400Hz aircraft AC power.
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Transformer and motors have a Volts/Hertz ratio that should not be exceeded. When some equipment is run on a different frequency, the voltage may have to be adjusted in the same ratio as the frequency.
What do you have to run?
Bill
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"Why not the best?"
Jimmy Carter
What do you have to run?
Bill
--------------------
"Why not the best?"
Jimmy Carter
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I assume that there is a power supply module that runs the rest of the system. In that sense, it more-or-less doesn't matter that it is an anemometer. Just need to make sure that the PS module itself will work. Can you provide any more information about the PS unit itself?
The approach we took when investigating the use of laptops on aircraft 400Hz power was to do a very careful and extensive ground test of the laptop PS brick by itself. We measured it six-ways-from-Sunday on normal 60Hz power, then gingerly connected it to 400 Hz power, and then repeated all the tests. We could detect no difference in any parameter. We then exercised it extensively for an extended period to make sure. Ideally we would have also disassembled one sample to confirm by analysis.
The approach we took when investigating the use of laptops on aircraft 400Hz power was to do a very careful and extensive ground test of the laptop PS brick by itself. We measured it six-ways-from-Sunday on normal 60Hz power, then gingerly connected it to 400 Hz power, and then repeated all the tests. We could detect no difference in any parameter. We then exercised it extensively for an extended period to make sure. Ideally we would have also disassembled one sample to confirm by analysis.
Hi Guys,
I have a question that I hope you can add some technical detail to. I'm an airline manager. We use laptops on our aircraft. There is an outlet in the aircraft rated at 120v / 225 VA / 400 HZ. Some of our pilots insist that plugging the laptops into this 400 HZ circuit is dangerous.
I was intrigued by VE1BLL's post where he indicates he was involved in some sort of study of just such an issue. VE1BLL, can you provide any more detail?
Also, do any of the rest of you have an opinion on the wisdom or technical issues of using a laptop charger on this circuit?
By the way, the charger is rated at 120/240 50/60 and 2.4 amps INPUT with a 19v / 4.2A output max.
Thanks for your replies
I have a question that I hope you can add some technical detail to. I'm an airline manager. We use laptops on our aircraft. There is an outlet in the aircraft rated at 120v / 225 VA / 400 HZ. Some of our pilots insist that plugging the laptops into this 400 HZ circuit is dangerous.
I was intrigued by VE1BLL's post where he indicates he was involved in some sort of study of just such an issue. VE1BLL, can you provide any more detail?
Also, do any of the rest of you have an opinion on the wisdom or technical issues of using a laptop charger on this circuit?
By the way, the charger is rated at 120/240 50/60 and 2.4 amps INPUT with a 19v / 4.2A output max.
Thanks for your replies
Excuse the thread hijack...
It's not 'is' dangerous. But it certainly is 'potentially' dangerous (which as you know, in aircraft terms, makes it a serious issue).
The overall approach we took was described in my previous post. More details: Our facility has 400Hz power. We made up an adapter cable so the laptop PS brick plug would fit the peculiar outlet used in our facility. Triple-checked the adapter for correct wiring. First we checked the laptop system on 60 Hz and measured brick output voltage and monitored the temperature. Then we gingerly (meaning, quite literally, standing back in case something 'interesting' happened) connected it to 400Hz. We could detect zero difference. We checked and checked and let it run for hours. No problem and no change was detected.
There remain some issues. The PN of the adapter should be controlled. The laptop maker might switch to a totally different PS supplier with no notification. People might purchase a replacement PS brick made who-knows-where.
Your pilots are correct to raise the issue. There are a wide range of possible solutions. We choose the simple ground test (including detailed measurements). Other options might include using a laptop brick designed for 400 Hz - I've seen them, but they're expensive. Or have a PS custom made, perhaps using 28VDC input to make it simpler. Or provide a 60 Hz inverter on the aircraft.
I should mention that even putting the laptops on the aircraft involved a lengthy process, including extensive E3 tests.
It's not 'is' dangerous. But it certainly is 'potentially' dangerous (which as you know, in aircraft terms, makes it a serious issue).
The overall approach we took was described in my previous post. More details: Our facility has 400Hz power. We made up an adapter cable so the laptop PS brick plug would fit the peculiar outlet used in our facility. Triple-checked the adapter for correct wiring. First we checked the laptop system on 60 Hz and measured brick output voltage and monitored the temperature. Then we gingerly (meaning, quite literally, standing back in case something 'interesting' happened) connected it to 400Hz. We could detect zero difference. We checked and checked and let it run for hours. No problem and no change was detected.
There remain some issues. The PN of the adapter should be controlled. The laptop maker might switch to a totally different PS supplier with no notification. People might purchase a replacement PS brick made who-knows-where.
Your pilots are correct to raise the issue. There are a wide range of possible solutions. We choose the simple ground test (including detailed measurements). Other options might include using a laptop brick designed for 400 Hz - I've seen them, but they're expensive. Or have a PS custom made, perhaps using 28VDC input to make it simpler. Or provide a 60 Hz inverter on the aircraft.
I should mention that even putting the laptops on the aircraft involved a lengthy process, including extensive E3 tests.
Generally it should be OK as it reduces the ripple on the front-end caps and is certainly not too fast for the front-end diodes.
The problem would come from newer, power factor correction models that may have active front ends. These can be run by software that wouldn't understand or possibly respond fast enough causing very interesting things to occur.
So either do exactly what VE1BLL suggests as in a full-on test or look for a replacement that states 400Hz on the label. I will say, that recently a lot more are being labeled as 47Hz-400Hz, probably because in most cases all it takes is a factory test to actually label it thusly, adding slightly to the market the company can reach.
Keith Cress
kcress -
The problem would come from newer, power factor correction models that may have active front ends. These can be run by software that wouldn't understand or possibly respond fast enough causing very interesting things to occur.
So either do exactly what VE1BLL suggests as in a full-on test or look for a replacement that states 400Hz on the label. I will say, that recently a lot more are being labeled as 47Hz-400Hz, probably because in most cases all it takes is a factory test to actually label it thusly, adding slightly to the market the company can reach.
Keith Cress
kcress -
Transformer-type power supplies (linear regulated supplies) will have a problem with 400 Hz power, but depending upon the transformer ratings may work fine with 50-Hz. Switch-mode power supplies will frequently work just fine with 400-Hz or 50-Hz power.
I once worked at a company where the product was rated 50/60/400 Hz. We sourced a new switcher supply of about 240 watts/three voltage outputs. The supply manufacturer did not rate it for 400 Hz and hadn't tested it for this, but indicated they couldn't see a technical reason it wouldn't work. We tested several supplies, and qualified them for application in our product. They worked just fine.
I once worked at a company where the product was rated 50/60/400 Hz. We sourced a new switcher supply of about 240 watts/three voltage outputs. The supply manufacturer did not rate it for 400 Hz and hadn't tested it for this, but indicated they couldn't see a technical reason it wouldn't work. We tested several supplies, and qualified them for application in our product. They worked just fine.
I have used Visicom Solid State frequency converters.
They seem to be well engineered, well built reliable units. One advantage is that, within specified limits, the 60 Hz frequency and voltage is ignored. You get very clean, stable 50 Hz power.
Visicom had an option I needed, Barbados is 120 VAC, 50 Hz [Yikes!] and I needed 120 VAC, 60 Hz.
They seem to be well engineered, well built reliable units. One advantage is that, within specified limits, the 60 Hz frequency and voltage is ignored. You get very clean, stable 50 Hz power.
Visicom had an option I needed, Barbados is 120 VAC, 50 Hz [Yikes!] and I needed 120 VAC, 60 Hz.
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