No. Everything works fine on a DBT when I tested it on my bench. But moving it to my main system has more current draw.
I use audio quest power cables and a Shunyata power conditioner.
I use audio quest power cables and a Shunyata power conditioner.
A single (if that's what you mean) 3A fuse sounds to small for feeding two 200VA transformers on what I assume is 120 volt mains.
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No thermistor for inrush is necessary, the current draw for the ACA is relatively small at ~20w per channel. Inrush is more a functin of your cap bank than the size of the transformer. If you find yourself blowing fuses, then either a slow-blow fuse or thermistor will help. A thermistor was REQUIRED for my Aleph-X monoblocks that draw 400w and have half a farad of capacitance each.
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When i rewired my power amp transformer from 220V to 110V, I blew fuses. I thought it was inrush due to the 110V. But it was not. I wired up the transformer primaries incorrectly.
Did the 3A fuse blow? Did you turn both switches on at the same time? If you turned on both switches at the same time, the inrush current may cause the 3A fuse to blow. It depends on the amount of capacitance you have and also the VA rating of your transformers. Large amounts of capacitance draw large amounts of current and high VA transformers allow large currents. When you tested with the DBT, current was limited by the DBT.
Thermistor for inrush limit should be in series (in line) with the switch, not across (parallel). Looking at your picture, I see something rectangular at the switches. A thermistor across the switch would defeat the switch and allow current flow. Is that possibly a capacitor?
If you have a large amount of capacitance and with 400VA total of transformer, the 3A fuse is on the low side. I would suggest a 3.5A or 4A slow blow. And please clarify the thermistor situation.
Yes. The 3A blew on the back of the external near the Inlet. but when I increase that, the 2.5A at each transformer blows.
I only flip one switch at at time.
I just checked on Mouser and the part I have installed is a safety capacitor. I wonder if that is my problem. Here is the link and a picture is below of how I have it installed.
R413F13300000M KEMET | Mouser
So, I need to find a way to incorporate a thermistor in a series with the mains... I have some CL-60 and wondering if I can incorporate those.
I only flip one switch at at time.
I just checked on Mouser and the part I have installed is a safety capacitor. I wonder if that is my problem. Here is the link and a picture is below of how I have it installed.
R413F13300000M KEMET | Mouser
So, I need to find a way to incorporate a thermistor in a series with the mains... I have some CL-60 and wondering if I can incorporate those.
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The capacitor should be installed across the hot and neutral AC lines, not across the switch.
Yes, if you have some CL-60, install one in series with each transformer primary. That will limit the current inrush.
Yes, if you have some CL-60, install one in series with each transformer primary. That will limit the current inrush.
Assuming the fuse is in series with the transformer primary, the thermistor should be connected between the fuse and the transformer.
I have each of the the transformer's red wires attached the fuse which are wired together then attached to the "L" on the inlet
The transformer's black wires are wired together then attached directly to "N" on the inlet.
So the fuses are only in line with each of the transformers primary RED wires...
The transformer's black wires are wired together then attached directly to "N" on the inlet.
So the fuses are only in line with each of the transformers primary RED wires...
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Where is the switch located? It should be inlet, then fuse, then switch, then CL60, then transformer primary.
It goes:
Inlet, fuse on back, then fuse for each primary, then switches for each primary, then each transformer primary is wired off the fuse.
The transformer black wires are all tied together hooked directly to neutral.
I can connect a CL60 right after the switches in between the switch and transformer primaries. So one CL60 for each switch between the switch output and transformer primary.
Inlet, fuse on back, then fuse for each primary, then switches for each primary, then each transformer primary is wired off the fuse.
The transformer black wires are all tied together hooked directly to neutral.
I can connect a CL60 right after the switches in between the switch and transformer primaries. So one CL60 for each switch between the switch output and transformer primary.
Look at the datasheet for your safety capacitor, it is not rated for in series with the mains.
Place it across the mains.
Place it across the mains.
Ok. I made the change to one transformer but wanted to make sure this looked correct.
Removed safety cap and put it across the mains.
Added a CL-60 after the switch into the transformer (red) primary.
All I have left would be to remove the safety cap from the other button and stash it away because I won’t need. Then just add a CL-60 between the switch and transformer.
Removed safety cap and put it across the mains.
Added a CL-60 after the switch into the transformer (red) primary.
All I have left would be to remove the safety cap from the other button and stash it away because I won’t need. Then just add a CL-60 between the switch and transformer.
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That should work. The thermistor will be hot during normal operation so it should be kept clear of anything flammable.
You may still need to increase the overall fuse from 3A to 3.5A or 4A.
You may still need to increase the overall fuse from 3A to 3.5A or 4A.
Ok. I tried the changes but it still blows the 2.5A before each transformer.
When I was testing on the bench I did NOT have the added 2.5A Fuses in front of each transformer which probably explains why each amp worked fine then.
Any harm in increasing the rear single fuse to 4A and increasing each fuse in front of each transformer to 2.75A or even 3A?
When I was testing on the bench I did NOT have the added 2.5A Fuses in front of each transformer which probably explains why each amp worked fine then.
Any harm in increasing the rear single fuse to 4A and increasing each fuse in front of each transformer to 2.75A or even 3A?
2.5A slow blow should be adequate for 200VA primary.
Perhaps there are issues with the power supply boards. Did you DBT test with the power supply connected to the amplifiers?
Perhaps there are issues with the power supply boards. Did you DBT test with the power supply connected to the amplifiers?
So, is this a dual mono setup? I hope you can get it working, and see how it sounds.