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what's the wattage for a laser printer transformer?

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rabbit51

Barker

Joined: Sep 29, 2003
Posts: 128

Status: Offline

Posted: Jan 23, 2009 - 08:39 AM
Post subject: what's the wattage for a laser printer transformer?

I have an old Samsung laser printer and according to the manual, the power consumption is only 45W, then I bought a 300W power transformer (220 to 110V), I'm not using it a lot (just printing few pages at a time), but after about 20 uses, it just burnt out, then I bought another one with 400W (for XBOX games), and it burnt the fuse (this one came with a fuse). So I'm just wondering if there's anyone using power transformer for laser printer and what's wattage required? I think it's probably the power surge during power up? but heck I'm using 300/400W, which must be enough!!!

ps: yeah, I know for those who're itching to say "BUY A NEW ONE", the trouble is I'm not using it a lot, just from time to time and the one I have is still quite new.

Thanks for your comment/suggestion.

CoffeeHawk_0
Board Deity

Joined: July 14, 2005
Posts: 17952

Posted: Jan 23, 2009 - 09:34 AM

look on the printer/Xbox or their power suppliers for the INPUT current (Amps, I) and voltage, multiply the 2 together and that's the minimum size for the transformer. (voltage times current = power (Watts)). Buy a little bit larger transformer to handle current spikes and for the longevity of the transformer. The earlier US Xbox360's required about 600W.

It is possible the printer requires a surge of current when it first starts up or begins to print, as do all motorized devices, that could blow the fuse if the transfomer to too 'exactly' sized for the use.

Andreas
Shanghai Royalty

Joined: Feb 27, 2004
Posts: 9140
Location: s/v Waratah

Posted: Jan 23, 2009 - 09:35 AM

The output of both the 300W, and the 400W should be more than enough for a 45W printer. Unless there is a malfunction in your printer, like a short circuit (full or partial). The only way to find out is by using a multimeter and measure amperage when the printer is plugged in, or measure the resistance of the printer when unplugged. The printer has an internal transformer as well, and I suspect that this one is giving trouble.

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DesertSpider
Post Boaster

Joined: Jan 19, 2007
Posts: 4725
Location: SHANGHAI, CHINA

Posted: Jan 23, 2009 - 10:06 AM

CoffeeHawk_0 wrote:

Coffee is correct, but I would use a safety factor of 2x to be safe (and if you have really expensive stuff, 3 or 5x, depending on the device).

CoffeeHawk_0
Board Deity

Joined: July 14, 2005
Posts: 17952

Posted: Jan 23, 2009 - 10:41 AM

45W seems low, that's less than 1/2 an Amp at 110V or less than a 1/4 Amp at 220V, definitely verify the wattage.

computersolutions

Veejay

Joined: July 02, 2006
Posts: 2049
Location: Shanghai
Status: Offline

Posted: Jan 23, 2009 - 05:35 PM

Laser printers draw a *lot* of ampage when warming up. A 400W PSU is nowhere near high enough. You should be looking at 2000W or 3000W realistically.

Given that a new laser printer can be had for 1000rmb or so, I'd just go with that. You're going to be spending that much for a decent power converter.

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DesertSpider
Post Boaster

Joined: Jan 19, 2007
Posts: 4725
Location: SHANGHAI, CHINA

Posted: Jan 23, 2009 - 05:59 PM

^ Doh. This is solid advice....

Stop tricking us with the crazy math problems and we might actually think for a minute.

Wink

computersolutions

Veejay

Joined: July 02, 2006
Posts: 2049
Location: Shanghai
Status: Offline

Posted: Jan 23, 2009 - 06:27 PM

After a bit more googling, I think you can probably get away with a 1000W psu, but I'd still lean towards 1500W to be safe.

I know you won't like this answer, but its probably better for you to buy another printer -
A cheap HP runs at 830RMB new

http://www.360buy.com/product/126739.html

Given the price of electricity in Shanghai, after a few months, your running costs for the transformer plus the price of a transformer for that wattage will easily run to that.
Plus the whole setup is going to be a lot safer.

Transformers run hot. And Ayi's have a tendency to blow up 110V stuff in the quest for plugs for the vacuum cleaner.

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CoffeeHawk_0
Board Deity

Joined: July 14, 2005
Posts: 17952

Posted: Jan 24, 2009 - 08:53 AM

Quote:

Transformers run hot

not if they are sized correctly when you are going from 220V to 110V Wink

When going from 110V to 220V, half the current is 'wasted' so those run hotter.

All the 'good' 800W or larger transformers come with on/off switches so they won't waste electricity when you're not using them.

Reasonable prices are about 35rmb for every 100W up to 1500W, but the 'real' price is even lower than that (if you have a local friend that can buy it for you).

Transformers are just 2 coils of wire and a diode in a box (+ a fuse and an on-off switch), there's nothing special or high-tech about them. The only difference between a 100W transformer and a 10,000W transformer is the size of the wire inside.

Post a picture of the voltage/power label on the back of the printer if you need more assistance.