Sloppy nameplates

[hillbilly1]

Had a tech concerned about voltage drop on a charging station, I had him send over a picture of the name plate.
100-240 volts 16 amps, really? 16 amps at what voltage? Second sloppy nameplate this week.

 

[kwired]

Best guess is it draws no more than 16 amps when operating at 100 volts.

Keeping same power level would mean 8 amps at 200 volts.

 

[petersonra]

I have been told this is a maximum current but it is longer at lower voltages.

 

[infinity]

No different than the nameplate on the AC unit on the side of the house.

 

[hillbilly1]

No different than the nameplate on the AC unit on the side of the house.

Haven’t seen an A/C unit say it works from 100-240 volt.

 

[kwired]

Haven’t seen an A/C unit say it works from 100-240 volt.

Not likely, but probably not impossible either. Especially if has a rectifier at the front end of the equipment.

 

[Frank DuVal]

Yep, switch mode power supply can operate over this large voltage range.

And a docking station would most likely have a switch mode power supply, like most computer equipment. Even if this does not dock a computer.

 

[hillbilly1]

Yep, switch mode power supply can operate over this large voltage range.

And a docking station would most likely have a switch mode power supply, like most computer equipment. Even if this does not dock a computer.

That doesn’t help figuring voltage drop, or even ocp. Should be in watts instead of having to assume 16 amps @100 volts.

 

[drcampbell]

Since it's a docking station, it might be the maximum current it can pass through, not the current it consumes by itself.

 

[Jraef]

That doesn’t help figuring voltage drop, or even ocp. Should be in watts instead of having to assume 16 amps @100 volts.

I agree. Too ambiguous. We can all agree on guessing what it MIGHT mean, but labels are not supposed to allow guessing. I'm surprised that UL allowed that, amkes me wonder if the UL listing is fake...

PS, no, it's legit, I checked on UL IQ

This is what their file says about marking though;

All power-supply types covered under this category are marked with input and output ratings that include the voltage and intended maximum load rating in amperes.

So I guess to the minimum letter of the requirement, it is marked with the voltage and INTENDED LOAD RATING in amperes. So I would take that to mean the OUTPUT is 16A maximum, regardless of the input voltage, which makes more sense, but is still lacking (lazy). I picked up my PC Power Supply and it tells me the DIFFERENCE between Input and Output ratings.

This is for a retail isle scanning robot, so most likely the batteries are 48VDC, at 16A = 768W, so even at 120V that's less than 7A. I wouldn't worry about VD on the feed to it.

 

[synchro]

Yep, switch mode power supply can operate over this large voltage range.

And a docking station would most likely have a switch mode power supply, like most computer equipment. Even if this does not dock a computer.

Yes, with a load like a battery that can accept a wide range of charging currents, a switched-mode power supply could be designed to draw a relatively constant current from an input over a 100-240VAC range. The battery charging current with 240V could then be as much as 240/100 = 2.4 times higher than at 100V. That way the charger could take full advantage of branch circuits that can supply 16A by reducing the charging time when higher supply voltages are available.
Or it could keep about the same output charging current over the 100-240V range, and then the maximum input current would go down below 16A as the input voltage is raised above 100V.
Or it could do something in the middle between these two modes of operation.

The labeling could certainly be more clear about this. I think you could use the 16A as a worst case in calculating the voltage drop. Then if the current goes down at higher supply voltages you'll just have a more conservative design.