Low voltage for motor powering
Low voltage for motor powering
(OP)
We are in the process of ordering a power tool for our on site installation service. The tool has a requirement of 1kW.
It was proposed to enquire for a 24V supply voltage for the following reasons:
24 Volt is standard instrumentation supply voltage so readily available on any process plant
24 Volt does not give any safty concerns.
But in my opinion for a power tool 24Volt is not enough. We would need much to high ampere rating (about 40amps) in order to run the equipment.
My Question: Am I right in this assumption?
Does anyone have experiences with running a motor with such low voltage?
Any other problems to consider? I presume the high AMP is a major issue on plants?
:)
It was proposed to enquire for a 24V supply voltage for the following reasons:
24 Volt is standard instrumentation supply voltage so readily available on any process plant
24 Volt does not give any safty concerns.
But in my opinion for a power tool 24Volt is not enough. We would need much to high ampere rating (about 40amps) in order to run the equipment.
My Question: Am I right in this assumption?
Does anyone have experiences with running a motor with such low voltage?
Any other problems to consider? I presume the high AMP is a major issue on plants?
:)





RE: Low voltage for motor powering
RE: Low voltage for motor powering
I would recommend that you Use standard equipment and supply voltages.
Best regards,
Mark Empson
http://www.lmphotonics.com
RE: Low voltage for motor powering
24 V dc may be the standard voltage, but trying to draw 40 A from the power supply is definitely non-standard.
If safety is the concern, put in a GFI breaker for the 120V supply.
RE: Low voltage for motor powering
Besides that, what davidbeach said is absolutely true. Plugging a power tool into a control power supply isn't a good idea, even if it is at the normal voltage. Power tools are notoriously noisy (electrically) and combined with the sudden power surge when you turn them on can cause other problems with the control equipment. I usually recommend to people that if they want a utility tool outlet, get a specific transformer or separate circuit for it. If you are in an area where you have 230V phase-to-neutral, use that.
JRaef.com
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RE: Low voltage for motor powering
what would be the implication if we connected it to the system. Would it trip because of the amperes drawn from it?
RE: Low voltage for motor powering
Mike Halloran
Pembroke Pines, FL, USA
RE: Low voltage for motor powering
RE: Low voltage for motor powering
Even the biggest 24V systems we occasionally see for substation tripping & control are no bigger than 24V / 40A. The cost of the cabling and the volt-drop problems make it impractical to go any bigger, and I don't particularly like them this big because of the over-sized cables which are required. High DC currents are generally bad news for controlgear too although at only 24V I guess you can use relays designed for heavy automotive applications, e.g.truck engine starter motors, etc.
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Sometimes I only open my mouth to swap feet...
RE: Low voltage for motor powering
Automotive winches are not noted for efficiency.
2 KW / 24 volts = 83 amps. At 80% efficiency, 104 amps.
Starting and or stalling, several hundred amps.
Wow, If your engineers designed the 24 V supplies with 200 A or 300 a excess capacity, by all means, go ahead.
Otherwise, either forget it or buy a model 8D battery, a hand cart to move it around, and a 40 amp charger to charge it at night.
respectfully
RE: Low voltage for motor powering
So it is a no go!
thanks
RE: Low voltage for motor powering
The battery suggestion was not meant as sarcasm. It was a serious suggestion.
respectfully
RE: Low voltage for motor powering
That's a fairly serious winch; it's going to have high starting current whether AC or DC powered. Almost by definition, winches have to start under full load.
Use during installation ( of ... something ) suggests that it may be most needed when the mains power is off.
Mike Halloran
Pembroke Pines, FL, USA