Car Power Inverters /Problem

[dmclambjr]

Question and Advice

Goal: To use a power inverter to power a printer in my car.

Problem: All three 12v power inverters I have tried, are producing about 94 vac. Which is too low to power the printer, the “input” rating on the printer electrical transformer is 100-240vac.

Printer Information: HP Deskjet D1660
Printer Transformer: Input Rage 100-240vac and Output 32volts dc @ 625mA

I have found from experimenting three things.
1: The actual dc voltage in my car is about 14.2 volts
2: When my car’s dc voltage is closer to 12volts (not 14v) the power inverters (all three I have tried) are producing about 110volts, which will power the printer and I don’t have any problems, but the cars voltage is never 12volts so the printer never works.
3. When dc voltage increases, my ac voltage decreases and when my dc voltage decreases the ac voltage increases.

Any advice or suggestions?

(Sorry for the repost, posted in Newsgroup yesterday, for some reason I was unable to post it here)

 

[Resqueline]

Very interesting. I'd have thought it would be the other way around..
I mean, the inverter would reflect the 12V value to a peak output value, and adjust its duty-cycle accordingly to make the RMS value 110V. The difference in measured value could be accounted for by the instrument not being true-RMS. The printer transformer makes use of the peak input voltage value (141-339V).

But if you are able to get hold of a 220V inverter that would surely take care of the problem.