Question on Inrush Current Limiter

[pwan]

Hello,

My friend is planning for Aleph 30 as he hasa 600VA transformer on hand. As the CL-60 maximum current rating is 5 Amp, he wonder if two/three CL-60s in parallel will work without using softstart circuit ?

Second question, in my mini-aleph (10 Watts, +/-18Vdc, 480VA tranf) why the CL-60 is getting extremely hot . Is it normal or dangerous?

Thanks!

[hifimaker]

The CL-60 does get very hot, and I believe one CL-60 will work for the Aleph30 if it is tuned for standard biasing.

-David

[sbear]

Depends on where you put the CL-60, before the transformer or after. Remember, just because it puts out 5A doesn't mean it's pulling 5A from the wall. The literature says the Aleph 30 pulls 200W from the mains, so 200W/120V (mains voltage here in the US, substitute your mains voltage)=1.66A from the wall here in the US, well within the 5A rating of the device. (I use one CL-60 in each of my Aleph-X 100W blocks, no problems)

But this is only if used as inrush protection on the primary side of the transformer, if you place them on the secondaries you would probably need to parallel them. But I also remember reading on the forum that you had to match them really closely if you did because one device would end up taking the most of the load otherwise.

As far as heat goes, they are supposed to get hot, that's why they work. By definition a CL-60 is a thermistor, a device that alters resistance with a change in temperature. As temp goes up, resistance goes down. (Mine get very hot as well)

Good luck

[jleaman]

Originally posted by dw8083
The CL-60 does get very hot, and I believe one CL-60 will work for the Aleph30 if it is tuned for standard biasing.

-David

He can also use more than 1. I used 2 on my aleph mini's because they share the same power input.

[pwan]

Originally posted by sbear
Depends on where you put the CL-60, before the transformer or after. Remember, just because it puts out 5A doesn't mean it's pulling 5A from the wall. The literature says the Aleph 30 pulls 200W from the mains, so 200W/120V (mains voltage here in the US, substitute your mains voltage)=1.66A from the wall here in the US, well within the 5A rating of the device. (I use one CL-60 in each of my Aleph-X 100W blocks, no problems)

I see. How about the inrush power during the power on ( 600VA/220V= 2.75-3.0 amp with big filtering caps)?

Originally posted by sbear

But this is only if used as inrush protection on the primary side of the transformer, if you place them on the secondaries you would probably need to parallel them. But I also remember reading on the forum that you had to match them really closely if you did because one device would end up taking the most of the load otherwise.

[/B]

I see. Will matching CL60 be just like measure their resistence (in Ohm) at room temperture? Will parallel multiple CL60 (say 3-4) at secondaries will increase margin of safty while still function?