Download `Onan` Gate Reactor 315-102

‘Onan’ ‘Magneciter’ ‘Gate Reactor’ part number 315-102 re-wind
Recommended is the use of heavy (leather?) gloves, safety-glasses, adequate breathing
protection (preferably a HEPA-rated air filtering breathing mask), and plenty of
ventilation away from other people, animals, etc.
A ‘Dremel’ high-speed very-thin ‘cutoff’ blade was used to carefully cut-through and
remove the factory insulation and wire windings. A fine-toothed hacksaw could certainly
also be used around the outside periphery, instead.
The ‘Core’ consists of a continuous ‘ribbon’ of magnetic steel wound around itself tightly
in a spiral. This then has a two-piece plastic insulating cover over it; and very messy
white silicone grease (as a heat conductor) inside the cover.
During the removal process, be aware and very careful to not cut through the inner plastic
core insulator; but, cut only just through the wire layers and remove. (This can be quite
difficult, as the wire/tape/varnish is factory-baked and very stiff, brittle, and potentially
dangerous to you and others, animals, equipment, – it can cut you, get into your eyes &
lungs, etc!)
Note how the factory attaches and anchors the ‘outside-connections’ (the “G1”, “G2”,
“C1”, & “C2” – labeled wire leads). Save those wire leads for finish-up use later, on the
new winding connections.
Appropriate ‘magnet wire’ and fiberglass tape (~1/2” wide) can be obtained at your
friendly local electric motor-winding/repair shop (if you have one); or ‘on-line’.
Heavy (Gate) winding is 510 turns (~255 feet) of #15 copper (symbol = Cu) ‘magnet’
wire, class 180 (type ‘H’), with “heavy” insulation [for 180-degree Celsius (Centigrade)
max operating temperature]. This is the first winding to install onto the prepared core.
Light (Control) winding is 170 turns (~85 feet) of #25 Cu ‘magnet’ wire, also class 180;
installed over the finished ‘Heavy’ winding.
Once the core is “cleaned-up”, a complete covering of fiberglass insulating tape is
installed upon it prior to application of the first (Heavy / Gate) wire winding. Use one
layer wound ‘around’ the outside circumference (lapped over the corners) of the core, and
individual pieces tightly adjacent to each other through the core hole (lapped over the
corners) making sure to completely cover the ‘sides’ too. This tape is to ‘cushion’ the
windings against insulation chafing during and after the winding process.
Do any wire winding in a very clean area with clean clothing, and clean hands, gloves,
tools, etc: Grit/dirt of any kind WILL cause premature failure of the winding insulation
during normal future use.
Wire is wound onto and through torroid cores by making a long – thin ‘shuttle’ onto
which the wire is ‘installed’, then the whole thing is ‘wound’ through and around the core
to do the actual winding (similar to a weaving shuttle – except always the same way,
NOT back and forth). (There are commercial toroid-winding machines made and
available -- IF you have the $10,000 + to buy one!)
The ‘shuttle’ used was about 3-feet long, about 1” wide, and about 1/8” thick, made of
stiff cardboard, with a half-‘H’ at each end (about ½” deep) to hold the wire in-place:
You MUST keep it TIGHT (use rubber bands on the shuttle) AT ALL TIMES during the
whole winding process!! This WILL take several hours, so -- allow plenty of
uninterrupted time!
Both windings should be wound in the same ‘through-hole direction’ (whether you go
‘right’ or ‘left’ along the core from your ‘start’ doesn’t really matter) to maintain
‘phasing’ easily [If you’re electrically/technically-inclined/knowledgeable, it doesn’t
need to matter at all; you can figure-out the ‘phasing’ later]. Beginnings (and/or endings)
of each winding must be phased the same; i.e., ‘G1’ & ‘C1’.
You’ll need to figure-out the phasing of the ‘S’ ‘winding’ (the unit ‘Sense’ wire) later,
upon installation of the ‘Gate Reactor’ onto the whole unit (see ‘Magneciter Troubleshooting Guide’ for either ‘low’ or ‘high’ voltage): The first time install of a re-wound
‘Gate Reactor’ was the ‘wrong way’: It produced 156 volts instead of the nominal 126
volts ‘no-load’. This required ‘flipping’ the ‘Gate Reactor’ around to get the “S” (Sense)
wire going through it the correct way.
The ‘Gate’ winding is now commenced to very carefully and tightly install 510 Turns of
the #15 Cu magnet wire around and through the magnetic core. Two “H”-shaped pieces
of thin (~1/8”) wood were cut-out (and smoothed with rounded corners) to snugly fit over
the core (through the hole) and used to move along as needed to control the ‘spread’ of
the wire over the core – there is very little room to get all 510 turns onto the core.
Additional space must be left for winding through with the shuttle; and, for additional
placement of the ‘Control’ winding later; along with space for the ‘sense’ wire, the
finishing tape, and the mounting bolt. Recommended is the use of 10 (ten) “subwindings” of 51-turns each evenly spaced around the inside (this is your limiting space)
of the core to complete the ‘Gate’ winding.
Another layer of insulating tape is then placed over (around) about 1/3 of the nowfinished ‘Gate’ winding.
The ‘Control’ winding (170 turns of #25 Cu ‘magnet’ wire – Class ‘H’ also) is now
commenced over the just-applied insulating tape.
The whole unit is then wrapped on the outside (and through the hole) with another layer
of insulating tape.
The ‘outside-leads’ are soldered and anchored; with a final tape wrap to finish-up (leave
space for the ‘S’ wire and through-bolt).
You may ‘test’ your re-wind job [use Test ‘Method – E’ first!!!], and use ‘as-is’, or; have
your ‘friendly – local’ motor repair shop ‘dip and bake’ for a factory-finish product to
keep wires from moving and chafing internally, and to minimize any potential for
moisture problems, and re-install;.
You are a glutton for ‘punishment’, if you try this, as this undertaking is very involved,
time-consuming; and can be very tricky and frustrating.