Isolation Transformer - Use with Cheater Plug
HHawk: I guess you missed Jea48's humour. Yes, you can still get a minor shock. The iso will reduce common mode noise in the AC line and reduce voltage spikes. Sizing is important. For both a preamp and amp, 1 KVA is minimal. You might want to do some search and research into "ground loop" Rives: You guessed right. Shhh. |
A balanced power system is still a grounded AC power system, (60/120Vac). True both 120V legs are ungrounded with a reference from each leg to the grounded neutral of 60V. The neutral is still connected to earth ground per NEC Article 647. ~ ====================== I originally had the pair plugged into the same outlet with the cheater plugs. (I did not have this problem until I replaced my previous power amp.) Without the cheater plugs, the hum is very loud. Hhawk, Are you saying with all the associated equipment, that is connected together by ics, plugged into the same outlet without using ground cheaters you get a loud hum? By Chance do you have a CATV system hooked up to the audio system in any way? |
Thx again. And the humor went over my head - I have no idea what you are talking about :) Jea48 - Yes, without the cheater plugs and even inserted into the same outlet I get the hum. I replaced a Parasound with a McCormack power amp and that started my having this problem. Cheater plugs do solve the problem but I had read where an isolation transformer might solve it as well and there would be no possibility of a nasty shock using that method. It appears from what you guys are telling me, it that I am still better off to have the pair plugged into the Tripp-lite using the cheater plugs than to go back to having the pair plugged directly into the outlet. It reduces the chance of a lethal shock. |
02-22-09: Hhawk Could very well be the source of the ground loop hum.... For lightning protection the SAT system has a lightning protection arrestor. The cable/s from the SAT dish connects to the arrestor then exits the arrestor and runs on into your home. Some SAT installers use an outside driven ground rod to connect the lightning arrestor to earth. This will cause ground loop hum. Temporarily disconnect the Directv ics from the preamp! Check for hum..... Still have hum? Just to make sure you are isolating the SAT 100% from your audio system disconnect the RG6 coax/s, (at the receiver), that comes from the dish to the SAT receiver. You may have two RG6 coaxes if you have a DVR. Post back the results. |
