Ill buy 2. Good idea.
Also if fuses are good I am game for that also.
Kris
As to Kris and Zed254
I am typing this in WordPerfect as this is easier for me to read while typing, to eliminate missing words and typos.
This text box on the webforum is to small for me to read while typing.
I am going to try to explain the purpose of this transformer in as simple terms as possible and answer the two questions as to the fuse and on how many transformers to buy.
When the Generator is first started in Start position, 24 VDC are applied to the two wires F1 and F2 through the Start / Stop / Run Switch Circuit and associated Relays.
This initial DC Voltage then creates the initial magnetic Field in the Generator G1 while the engine is still cranking.
This initial Voltage is around 15 to 20 VAC while cranking
The transformer is directly connected with its primary Coil to L1 and L2 Output power hence the transformer starts supplying the Voltage Regulator Board with AC Power
Part of this power is also fed back into F1 via the center tap of the secondary side of the transformer.
F2 is tied to ground
As the Generator is revving up, the voltage on the primary side increases with increase in rpm,
this increases the supply voltage to the VR Board and F1 when the Start Switch is released,
the 24 V on F1 / F2 are removed and the unit is sustaining it self .
The combination of input voltage on the primary side of the transformer and power output on the secondary side supplying the VR Board and this creates now a constant voltage on F1 while the system is running.
Increasing the Voltage via the Voltage Rheostat / VR Board increases the Voltage on F1 and lowering the Voltage via the Voltage Rheostat / VR Board decreases the Voltage on F1 and so forth.
So far with the functioning of this circuit.As to the fuse. Yes on the primary side. A 3AG Type Fuse with about 5 Amps should protect the Transformer, VR Board and exciter coil it self.
All newer Gensets have this fuse. You can get a panel mount 3AG Fuse Holder and mount it next to the J13 Receptacle on A11 and label it.
With this fuse, there should be no need for a second transformer, as the fuse will blow now, cutting of power to the transformer itself when something goes wrong on the secondary side.
In Kris’s case, since the unit is no longer self sustaining after the Start/Stop/Run Switch has been released indicates a double failure:
1. The transformer overloaded due to a short on the secondary side and burnt out because there was no fuse protecting it
2. One cause of this short has been ruled out due to resistance check - the exciter coil
3. This leaves only the Voltage Regulator Board as suspect. The transistor Q5 and/or the 2 SCR’s are blown and have shorted.
This is the most likely scenario at this point. There is nothing else connected to the secondary besides the items listed above which can cause a short.