ds54 power supply

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The manual for the DS54 says to use a power supply 12 to 16 vac at least 500ma I found a power supply 16.5vac 1 amp. It throws the atlas switches better than a 12vac, is it okay to use it even if it is more than 16vac?

-- jerry ernst (jerbear@execpc.com), March 25, 1999



I would go ahead and use your 16.5 Vac transformer. When Digitrax says use 12-16V, there is still some margin built into that - meaning you can go above 16V and not blow it up. There is probably several volts of margin built in. Possibly even quite a bit! The next time I talk to AJ, I'll ask.

There has to be some margin since any "16V" transformer will put out more or less depending on the incoming line voltage. While your incoming power is supposed to be something like 115V, it can vary between 105V and 130V. Your power company generally does a good job of keeping it between 115V and 120V. If your incoming voltage was 125V, your transformer would be putting out over 17V.

You didn't ask if the amperage of your transformer was too high. This is a common question. So if not for you, I'll answer this question just in case someone is out there wondering.

The answer is no. Having a transformer that can put out more current than you need is never a problem. It might be overkill, but it will not hurt anything as long as you fuse it appropriately. The reason is that a circuit will not draw more than it needs. If something is rated at draw a maximum of 1/2 amp, that is all it will draw - unless something goes wrong. That's what fuses are for!

-- Allan Gartner (wire4dcc@aol.com), March 27, 1999.

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