G8MNY > TECH 21.04.25 07:30z 121 Lines 6734 Bytes #182 (0) @ WW
BID : 30780_GB7CIP
Read: GUEST
Subj: MEDUSA SIP2300 Generator info
Path: ED1ZAC<ED1ZAC<GB7CIP
Sent: 250421/0730Z @:GB7CIP.#32.GBR.EURO #:30780 [Caterham Surrey GBR]
From: G8MNY@GB7CIP.#32.GBR.EURO
To : TECH@WW
By G8MNY (Updated Jul 13)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)
Years ago I bought a MEDUSA SIP2300 4 stroke petrol generators as the were so
cheap (just in case we have power cuts!). It's the seems same as WOLF2.3kW.
It is fairly quiet @ 73dBA @ 4m. The large 12 l tank gives approx. 10 hours run
time. It is not too heavy @ 83kg full, 41kg dry. So to move it by oneself (only
on and off a low level trolley & lift into van etc!)
Gauge Filler
ÜÜßßßßßßßßßßßßßßßÜÜ Û _.==ÄÄÄÄÄðððððÄÄÄÄÄÄ.._ Û Tube
Û/~~~~~~Tank~~~~~~~\Û Û/" Large 12L Tank "\Û Cage
Û-------------------Û Fuel Tap Û===========================Û
Û\_____________/~~~~Û & filter\Û|"""""~~~~~~~~~~~~~~~"""""|Û
Û Tap(0) ³elec Û STOPÛÞ [] øOK ³ on³ " AC " ÝÛ AC
ÛChoke // Sol\____Û SWITCHÛ |_ øOil³ º ³ = = = = _| Û 2x13A
ÛÚÄÄÄÄ¿ /~~~~~\\. ÛPull Û³~~""---..........---""~~³³Û
Û³In- ³,' /~~~\//\\ ÛStart Û³F ³ENGINE | | ³³Û
Û³Take³³ ³ ( ) ³ ³ Û Û³A ³ (=)oil ALT | ³³Û
ÛÀÄÄÄÄÙ \ \___/ / Û Û³N ³ _____³_³__|_____| ³³Û
Û Ú' ÚÄÄÄÄÄ¿ `¿ Û ÛÀÄÄÁÄÄÜÙ ÀÜÁÄÄÄÁÙÛ
ß"""""""""""""""""""ß ßßßßßßßßßßßßßßßßßßßßßßßßßßß
I have modified it for /P contesting, to power several 400W valve PAs for as
per my bul on "Petrol Gennys for /P SSB". With my rev up modification (add a
solenoid for FEED FORWARD load compensation) the measured performance is now...
Generator Unmodified Modified
Load kW Volts Hz Volts Hz Uplift %
0 255 55 255 55 0
0.1 235 54 238 54 0.3
1.0 225 53 234 54 4
2.0 Rated 215 51 235 54 6.4
2.3 Old Peak 200 49 233 54 16.5
2.5 190 47 235 54 23.7
3.0 New peak 180 45 33% throttle 220 54 22.2 @ FULL THROTTLE!
I do not intend continuous loads over 2kW, just speech peaks etc. to go to 3kW
peak load. Before the modification it was not possible to activate the 10A
thermal output trip on good power factor loads, after this modification it is
now possible!
At 50Hz you only get 220V output, but it is more economical to use lower RPM if
the peak power is not needed! There is no 2 speed option for this generator,
but a long screwdriver will adjust the voltage/RPM setting spring OK. Note the
off load voltage is quite a bit higher than even with a base load of 100W lamp.
Other Mods I did were..
1/ Added earth bonding from engine, to frame, and to electric panel plate.
2/ Added earth lead & earth clip for external earth stake.
3/ Added engine ignition lead screening, & made a screen tube for the plug cap.
4/ Painted Alternator casing black to improve heat dissipation.
CIRCUIT
I have reverse engineered the diagram...
STOP
ÚÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂo/oÂÄÄÂÄÄ¿
³gn/ye ³ 2x13A ÃÄÄÄÄÄ¿front External Earth ³ ³ ³ ³
³ E AC E _³_panel ³ ³ ³ ³
³ bk N L N L /// ³ ³ ³ ³
³ ÚÄÄ´ ÃÄÄÄÄÄ)ÄÄÄÙ Ú - - - - - - - - - - - - - - ¿ ³ ³ ³ ³
³ ³ ÀÄÄÄ)ÄÄÄÄÄ´ | ÚÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´<ÃÄÄÄÄÙ ³ ³ ³
³ Run ³ ³ | _³_D2³ ³ D1 | ³ ³ ³
³ Neon 10A ³ | /_\ _³_ _³_ | bk/³ ³ ³
³ ³ Trip ³bk | ³ \_/Q2 Q1\_/ | wh³ ³ ³
³ ÀÄÄÄÄÄÄ´ ³ | ³ ³\ ÚZD ____/³ | ³ ³ ³
³ ³rd ³ Added | ³ ³ Ã47RÄ´<ÃÄ´ ÃÄÄÄÄÄÄÄÄÄÄÄÙ ³ ³
³ 25u 450V ³ ³Solenoid | ³ ³ ³ ÀÄ200R´ | Oil ³
³ ÚÄ´ÃÄ¿(155V)³ ÀÄÄÄÄÄÄÄ¿ | 50R ³ ÀÄÂÄÄÂÄÄÂÄÄÄ¿ +³C1 | Neon ³
³ ³ ³ ³ ===== ³ | ³ ³ _³_ 1K ³C2 ³ ===47u | ³ ³
³ ³ ³ ³ _(((()_³ | ³ ³D3/_\ ³ === 2K ³63V | ye ³ ³
³ ³ye ³ye ³ ³ 0R2 | ÀÄÄÄÁÄÄÄÁÄÄÁÄÄÁÄÄÄ)ÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ ³
³ ³ ³ ³ ³ | P C B ³ | ³
³_ ³_ _ ³_ _ _ ³ _ _ ³ _ _ _ _ _|_ _ _ _ _ _ _ _ _ _ ³ _ _ _ _| _ _ _ _ _ ³
³ ³or ³or ³rd ³bk | __ oil bk³ bk/wh ³
³ ³1R4 ³ ³ 1R8 ³ | Timing |( ÃÄo/oÄÂÄÄÄÄÄÄÄÙ Ú5KÄÄÄÄ¿ ³
_³_ À((()Ù ==== À(((()Ù | Pickup |( ÀÄ´ÃÄÄÙ Spark ||(6K ³
/// ==== Ú(((()¿ ==== | -2V _³_ 1n ? Plug ||(___³
ÀÄ´>ÃÄÙ | /// ||( 1R
A L T E R N A T O R | C R A N K C A S E M A G N E T O _³_
| ÚÄÄÄÄÄÄÄÄÄ¿ ///
TUBE_³_ gn/ye _³_ FAN
FRAME/// /// COWLING
EXCITATION
This is a brushless excitation with the rotor magnetically charged up each half
cycle from circulating 90ø out of phase currents from the exciting capacitor.
In the rotor is 4x 3A 200V diodes in series parallel (a small back EMF R)
across the winding to maintain the current half a cycle after the kick. This
system is more reliable than brushes, but does produce a kink in the output
winding waveform.
ELECTRONIC IGNITION
The electronic ignition works in a strange way, as top dead centre approaches a
voltage of -80V or so is made by the magneto primary, this is shorted out when
the timing pulse triggers the SCR, shorting this voltage & producing an
ignition voltage in the magneto secondary.
Only one wire from the crankcase may be just the oil status. The -ve EMF of
magneto appears on Q1 SCR cathode gate and positive going on the gate via D3
47R & ZD, to fire SCR Q1 and short out the coil producing a voltage pulse on
the secondary that makes the plug spark. If there is no oil Q2 is not fired and
C1 charges up to light the low oil neon and eventually defeat the ignition
after 30 seconds. But I have found in practice that at the point of low oil
occurring when running, there is intermittent ignition (hunting on and off)
rate than a shut off!
(this understanding follows feedback from internet reader Richard Groves)
See my TECH buls "MEDUSA SIP2300 Generator Repairs", "PERFORMANCE POWER 1kW
Genny" & "Petrol Generators for /P SSB".
Y Don't U send an interesting bul?
73 de John G8MNY @ GB7CIP
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