DIYAPASON-L Digest #52 - Saturday, March 4, 2000
 
Re: Fw: [Residence Organs]  Mixture Chest
  by "Jon" <sparky@chesco.com>
Amperes! Was Mixture Chest
  by <TheGluePot@aol.com>
 

(back) Subject: Re: Fw: [Residence Organs] Mixture Chest From: "Jon" <sparky@chesco.com> Date: Sat, 4 Mar 2000 09:56:57 -0500   Hmmm all this talk about current makes me laugh... my moller supply can melt the insulation off 10 gauge wire in 3 seconds... any idea what the current would be on that?   jon   PS THis is the supply i posted to the list about several months ago with the rewired saturable reactor and 500Kuf caps     >VEAGUE wrote: > >> All this voltage talk....don't forget Wicks- and others- use tremendous >> current. Gotta have those amps, baby! >> > >You are starting to get me concerned that my two 20-amp Durst rectifiers >may not be enough for the >8-10 ranks of direct electric chests I eventually hope to have for my >unified (unitified? ;-) home >organ. > >Should I be thinking about getting more amps for this system? > >Mac Hayes > > > >DIYAPASON-L: a Discussion list for owners and builders of their own >Residence Pipe Organs. >HOMEPAGE : http://www.diyapason.pipechat.org >List: mailto:DIYAPASON-L@pipechat.org >Administration: mailto:owner-DIYAPASON@pipechat.org        
(back) Subject: Amperes! Was Mixture Chest From: <TheGluePot@aol.com> Date: Sat, 4 Mar 2000 11:00:12 EST   > You are starting to get me concerned that my two 20-amp Durst = rectifiers may not > be enough for the 8-10 ranks of direct electric chests I = eventually hope to have for > my unified (unitified? ;-) home organ. > Should I be thinking about getting more amps for this system? > Mac Hayes >>   As a professional organ builder I always compute the maximum number of = keys down with couplers on to get how many chest magnets are involved then add shutters opens, pistons pushed, console lights on, and every other current =   eating mechanism thrown in. Current is additive. If you have direct electric action with each magnet drawing 0.5 Amps and 40 chest magnets = will be playing then 20 Amps will be drawn. Your possibly unbalanced 20 + 20 = Amp supply may burn your house down unless you have fuses on them, both on the =   input and output sides. For a non-unified organ figure a 3 note chord playing 10 ranks gives you 30 magnets on plus the next manual playing 3 = notes on 5 ranks adds another 15 Amps and 2 notes on the pedal with 3 ranks give = a total of 41 magnets at 0.5 Amp or 20.5 Amp total. You haven't even = started with stop magnets, console lights, shutter magnets, the Zimblestern motor, =   etc., and already your rectifiers are at half output. Add a coupler to = each manual and the current jumps to 41 Amps. An electromechanical relay would =   just add many more Amps being drawn. Unified organs can add many more = chest magnets into the current draw. The rectifiers quickly become crispy critters! Without fuses and by having too small wires in the organ could mean your calling the fire department. One thing to remember, organs are considered to be part of the house they are installed in, thus negating = your homeowners insurance by having illegal non-code wiring installed. After = the fire your insurance policy is null and void.   Once I compute the maximum I then double it. Fuses are always put on = every single rank return wire and applied liberally within the instrument on a central fuse board next to the relay. Every wire is tagged so as to be identified. The higher voltage fuses for the line currents are all in national electrical code approved boxes installed by licensed electricians =   (and double checked by myself) under a building permit from the local = county or municipality. The insurance company is notified of the installation = and thus the homeowner is covered. Many times the instrument is put on as an extension to the policy so it is covered also.   Al Sefl