Walter Woods tech ?'s

Hey guys, maybe you can help me out here:

1. Does anyone know the amount of current inrush there is with a Walter Woods Ultra? I can't measure it with a multi-meter, right? I don't know anyone close by that has the proper gear. I first became aware of inrush when I got a Stewart 2.1. It has tripped breakers dozens of times whenever I first plugged it in. My tech in KC told me that the 2.1's inrush regularly exceeded 15 amps. Unlike the Stewart that initially draws power when its' power cord first being connected to mains, the WW exhibits current inrush only after I engage the power switch. There seems to be no noticeable inrush when I first plug it in.

2. Is it safe to run a WW without a speaker load connected to the outputs? Sometime I want to be able to use the WW just as a preamp. I searched and couldn't find anything specific. I would assume it would be okay but you never know.

3. A related question: Should the amp be off when I'm inserting and removing speaker leads from the amp or the cabinets? I know Acoustic Image warns that their amps can be damaged if you short the connection, something apparently easy to do with a 1/4" when it's moving through a jack. I'm not sure if that's something I have to worry about with the WW. When I'm testing cabs it becomes a pain to have to power it up and down all the time plus I worry about that not being good for the amp, either. Thanks!

-Brad

 

Ken, before I just now looked for a definition, I knew inrush to be the amount of current that is drawn into the unit to charge the various capacitors and such so that the amp is ready to perform.

As I understand it, the Stewarts latch onto the main AC as soon as you plug it in whereas most units start drawing only after the unit is turned on. The Stewart's instructions state that about one minute is needed after you plug it in for the amp to bring itself into "ready" mode.

After doing a search I came up with this:

From www.systemconnection.com/downloads/poweradapterkb/switchingtransfo.html
"When a power supply is first turned on there are a lot of capacitors and inductors that are empty. Inrush current is the transient amount of current that it takes to charge these capacitors and inductors and thus start up the power supply."

And from Wikipedia
"Inrush current or input surge current refers to the maximum, instantaneous input current drawn by an electrical device when first turned on. For example, incandescent light bulbs have high inrush currents until their filaments warm up and their resistance increases. Power converters also feature high inrush currents relative to their steady state currents. This is typically the charging current of the input capacitance."

zombywoof: Yes, I've tried the power strip trick to no avail. Again, this isn't something that's happening every time. I hardly ever use it anymore so I don't deal with it much. I even had trouble with it plugged into a Furman AR-1215 voltage regulator. I would plug it into the unit and then turn on the regulator and sometimes it would still trip a breaker.

Thanks, guys!

 

Oh and BTW, no problems whatsoever with my WW! She runs clean as Willie's veggie car!