RadioBanter - Power amps/watts consumption query?

On Feb 9, 1:45*pm, David wrote:
dxAce wrote:

David wrote:

wrote:
I would be grateful for the advice of one of our technically minded
members:
The new radio I have coming merely states it's power consumption as
210VA, as it is a multivoltage radio.

What consumption in watts/amps does this translate to at 240 volts AC
mains?
Also. if I used an inverter to drive it off a 12 volt DC battery, what
would the power consumption in amps then be?

A friend who helped me wrote:
Watts = Volts * Amperes so 210VA = 210 Watts

210 Watts means 210 / 240 Amps which is .875 Amps.

If you want to use a 12V battery, 210 Watts means 210 / 12 Amps or
17.5 Amps. This assumes the AC supply is as efficient as the DC
supply. It won't actually be quite as efficient, so you're likely to
need fewer Amps, maybe 14 or 15 but that's a guess. Maybe you can ask
as the DC current depends on their design which is not known to us
yet.

Those numbers look very high to me. I suspect they've made a little
mistake.

I replied:
it does seem very high to me for 210VA. at 240 volts AC mains.
As just a poor guess I would estimate
0.5 amps at 240 volts AC mains
and 8 amps at 12v DC
but I cannot calculate it.
_______________________________

So what do the experts out there think?

Would be grateful for your help.

John Plimmer, Montagu, Western Cape Province, South Africa
South 33 d 47 m 32 s, East 20 d 07 m 32 s
RX Icom IC-756 PRO III with MW mods
Drake SW8 & ERGO software
Sony 7600D, GE SRIII, Redsun RP2100
BW XCR 30, Sangean 803A.
Antenna's RF Systems DX 1 Pro Mk II, Datong AD-270
Kiwa MW Loop, PAORDT Roelof mini-whip
http://www.dxing.info/about/dxers/plimmer.dx

That's key-down CW right? *Worst case?

If you're going to be just listening or working SSB your power
consumption will be much less.

Probably drawing at *least* 2 amps on receive. And, that puppy is capable of 200
W output. With transceivers that put out only 100 W one had best have *at least*
a 20 amp supply. *I realize that the '7700 is not capable of DC operation, but
that gives you some idea of power consumption.

Just a thought, but you might peruse the Universal catalogue and look at the
power consumption of *similar* rigs.

dxAce
Michigan
USA

- Seems a tad on the wasteful side.

David,

It's a Transceiver that has both the Receive and Transmit
Sections {Except maybe the Finals} Powered-Up {Active}
or in Stand-by {Waiting} all the time that the Transceiver
as a 'unit' is turned ON.

If as JP has said : That he can Lock-Out {Shut-Down}
the Transmitter Section then he may be able to reduce
the Receive Power Consumption in the Stand-by Mode.

Rx Stand-by 200 VA (typ.) {Receive Only Listening Mode}

Max. Audio 210 VA (typ.) {Receive Only Maximum Audio Output}

I have to think that about have of the Power being used
in the Stand-by Mode is Transmitter specific and if the
Transmitter Section could be De-Powered; then the overall
Power Consumption could be reduced for "Receive Only" use.

~ RHF