Dedicated Line Advise
Lowrider - if your panel is like mine (i.e. a two bank North American panel ) - the adjacent switches in each "bank" of switches (i.e. if you have multiple banks) alternate between the two phases - e.g. BANK "A" BANK "B" Switch # Phase Switch # Phase 1 A 15 B 2 B 16 A 3 A 17 B 4 B 18 A 5 A 19 B etc... For your two phase devices you will see a "linked switch PAIR" which takes two adjacent spots - one switch of the pair is connected to phase A and the other connected to phase B (or vice-versa) You need to make sure the electrician knows you require both lines on the same phase. He/she should understand how to connect to the same phase FYI - It only takes one two phase device to "pollute" both phases - so your goose is cooked - along with most other North American homes. The only real protection against noise introduced by two phase devices is to get 1. an Equitech transformer $$$. 2. a power re-generator I would not be too worried - unless the power in your area is prone to brown outs or surges, the noise from the furnace switch dissipates really quickly down the power-bus Which switch bank is immaterial, but the farther away from the two-phase device switches the better This link shows you a typical two-phase panel layout https://www.google.ca/search?q=two+phase+house+distribution+panel+pic&num=20&tbm=isch&tb... Regards... |
forgot to add, the most noise you will hear from two phase motors is when they turn off and on, normally via a solenoid relay. Any more than that and I would co sider having the motor replaced - it's past its prime. My furnace has a setting that runs the fan at a low speed all the time. so there is no switching as such and no high current spikes on the supply, which can cause a brief voltage drop, depending on your supply. regards |
Lowrider - The box you have is just another variant of a two phase supply. The electrician will simply use two switches and ensure they are on the same phase - e.g. switch positions 7 and 8 or 9 and 10 (assuming they are available.) It does not matter which phase they are located on, as long as they are both on the same phase. Some people believe having outlets on different phases do not improve SQ - HOWEVER, from a safety perspective, havin all components on a single phase is safer should one component fail, there is no risk of exposure to voltages across two different phases, which is much more dangerous Placing the new breakers at position 19 & 20 will ensure they are located as far as possible from the noisy appliance breakers. A separate breaker panel just for the audio circuits might be the quietest solution - but more expensive Regards... |
Lowrider - in your depiction of your panel - for two lines on the same phase.... You would have one switch on 19 and the other on 20 - which would be PHASE B Alternatively, you could have the switches placed at locations 17 and 18 - which would be on PHASE A Either option is OK - just keep these switches away from the two phase switch-pairs Regards... |
Lowrider - since you will be juggleing swtches - I believe the best place for the two phase switches will be closest to the end of the panel where the incoming wire connects to it - that way any noise will dissipate back to the supply The audio switches would be at the opposite end farthest away from the two phase switches. One other thing - ensure the electrician maintains the "power balance" between the two phases Regards... |
Minorl - my only preference for keeping the gear on the same phase is for safety only. In the event of some very rare condition(s) occurring in audio components, having the components split between two phases could result in (and I stress very rare and could) - a voltage difference between present on the chassis of two components of 240 volts and not 120 volts if the components were on the same phase. e.g. I’ve read of members "removing the ground pin" in order to get rid of hum - this is one action that I believe can have dire consequences, since it defeats the purpose of the ground wide in that components - the chassis could become live if something inside fails. e.g. I’ve also experience third party power cables that were wired incorrectly, i.e. the live wire went to the neutral side of the IEC connector, which, from the perspective of AC makes no difference in operation - however from a safety perspective it could mean that the neutral side of the input to the power supply is live. Most of these issues may not impact general component operation, but there are design standards for a reason - safety! I also believe there are other factors pertaining to the age of the external supply lines and transformers that might result in noise being transferred to the components, but that may only occur when the electrical infrastructure is old - which does not apply in this case. Won't happen? - maybe not, but I've lost count of the number of musicians that have been electrocuted from what was supposed to be - safe amplification I also do not wish to start a debate - but I thought I would provide the above info for everyone’s consideration. BTW - I’m also in the EE camp :-) Cheers |
