ESP sound soft start

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi folks I hope I'm in the right place...

I've got one of these 'ere soft start PCBs from ESP.

I am building a dual mono power amp, including 2x 430VA transformers each feeding 4x 10,000 uF filter caps.

Simple question: is the 'standard' Rod Elliot design (10A relays, 50R dissipating resistance and 4.6A inrush limit suitable for regulating the supply to BOTH transformers?

Or... should I fit a pin compatible 16A relay and reduce the dissipating resistance so that I get about 14 A during the 100 ms limiting period, 7A per toroid.

I would prefer the filter caps to get as much energy as possible during the initial 100 ms limiting period whilst staying below 400% of the max continuous current for the toroids. If I use Rod's standard 50R design then my current will be limited at just 130% of my combined max cont. rating.

And finally... is the ESP PCB rated for 14A? Mains track width is 2.5 mm but I'm measuring 0.1 Ohms resistance for the mains tracks.
 
Member
Joined 2010
Paid Member
.......And finally... is the ESP PCB rated for 14A? Mains track width is 2.5 mm but I'm measuring 0.1 Ohms resistance for the mains tracks.
0.1 ohms is possibly the lowest value that can be displayed and the resistance of any probe leads is probably in the region of 0.1 ohms too. Have you simply shorted the probes and taken a reading to check?
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.