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Home: Video University Forums: Wedding & Event Videography:
Anyone know electricity?

Brackish
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Jul 14, 2009, 7:48 PM

Post #1 of 6 (784 views)
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Anyone know electricity?	Can't Post

I've got two AC power adaptors/battery chargers with similar specs,
for Sony cams. Can anyone tell me what might be the difference,
if there is one?

Unit A
"AC IN" 100-240V 50/60Hz 18W

"DC OUT" 8.4V 1.5A

Unit B
"AC IN" 100-240V 50/60Hz 23W

"DC OUT" 8.4V 1.5A

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"still motion is who everyone else is trying to be like"

Bob A
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Jul 14, 2009, 8:46 PM

Post #2 of 6 (767 views)
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Re: [Brackish] Anyone know electricity? [In reply to]	Can't Post

There are a couple methods of converting AC to DC. The first uses a transformer to isolate the AC input and reduce the voltage which is then rectified with diodes or chips and filtered and maybe regulated to produce the desired output. These have been around for many years and most converters use that method. The second, newer type, uses 'high speed switching' which basically turns off and on very fast making the resultant desired DC. The second type is very light in weight as it does not need a transformer and is very efficient. The H.S.S. supplies provides a square wave output but does not seem to bother any equipment or produce 'noise'
There are varying designs and varying efficiencies in both types which account for the slightly different input wattages. When a unit has "100 to 240 VAC" input without any kind of voltage switch, it is the second type of supply which are generally the better in efficiency and very long lived.
There is no advantage or disadvantage in either of the 2 specs you mentioned.

Brackish
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Jul 15, 2009, 2:20 PM

Post #3 of 6 (721 views)
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Re: [Bob A] Anyone know electricity? [In reply to]	Can't Post

Thanks. I guess the 18W vs. 23W makes no difference then.

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"still motion is who everyone else is trying to be like"

Bob A
Veteran

Jul 15, 2009, 2:52 PM

Post #4 of 6 (717 views)
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Re: [Brackish] Anyone know electricity? [In reply to]	Can't Post

Nope, no functional difference at all. If you were to mesure the input current of the 2 they may be a lot closer than the specs say. The specs are often calculated rather than an actual measurment.

ValleyVideo
User

Jul 23, 2009, 7:35 PM

Post #5 of 6 (586 views)
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Re: [Brackish] Anyone know electricity? [In reply to]	Can't Post

For DC power, P = i V (power = current x Voltage)
and both adapters are stating the same current (i=1.5A) and Voltage (V=8.4V)

My guess is the Power rating (Watts) shown is a maximum "full load" power consumption, and accounts for losses within the adapter itself. Nominally, each would consume about 12.6W.

Regardless, I second the others that if the plug fits, you can interchange them.

Justin

thatmdvideoguy
Veteran

Jul 24, 2009, 10:13 AM

Post #6 of 6 (565 views)
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Re: [ValleyVideo] Anyone know electricity? [In reply to]	Can't Post

The most important thing is that the DC connectors are both the same! If a positive center pin is needed, check to insure this is the configuration. There is usually a little diagram on the case indicating pin polarity.

Allan