Fun Projects 5055 Cut-Out

[Rodger Erickson]

I recently acquired a used 5055 solid state cutout from Fun Projects - I'm assuming it's basically a diode with some sort of crowbar circuit to prevent a runaway condition. It seems to have a diode drop in the forward direction and a high resistance in the reverse direction. Does anyone have any recommendations on how to further test it to make sure it's OK to use?

5055.jpg

[TRDxB2]

Take your pick
https://www.google.com/search?client=fi ... ing+a+diod

Your test says its likely Okay "If you have continuity in both directions, the diode is likely shorted"

[Ron Patterson]

If I am not mistaken that is a Fun Projects Voltage Regulator. NOT a cutout.
Ask someone on this Forum to send you a copy of the Installation Instructions and follow them to the letter!
Ron Patterson

[AdminJeff]

Ron is correct. 5055 is a Voltage Regulator.

Try it.... you cant hurt anything. Here are the original FP instructions:

WARNING!! - This voltage regulator is for use on standard Ford Model T 6 volt negative
ground generator/12 volt battery systems only. Permanent damage will result if the voltage
regulator is connected even momentarily to any other system. Check which post of the battery is
connected to the car ground (frame). If the negative (-) terminal is not connected to the frame then
you do not have the correct voltage regulator or your battery is installed incorrectly!! Do not attempt
to proceed until the battery is installed properly!! Follow all instructions carefully or you will destroy your new
regulator.
Never short the voltage regulator terminals together as with a jumper wire to test the operation
of the regulator or to flash the generator - The voltage regulator will be damaged. Remove the
voltage regulator from the generator before performing any tests on the generator.
Proper operation of the voltage regulator requires a proper setting of the generator third brush. It is
assumed that a good battery and a good generator have already been properly installed on the car
and that the main generator brush assembly has been installed and adjusted properly. A voltage
regulator is not a cure for a sick generator or sick battery. A voltage regulator is a great
improvement to a good electrical system. Only the generator third brush assembly will be
adjusted and under no circumstances should the third brush assembly be set for more than 8
Amps of charge.
Make certain that all electrical connections in the car are clean and tight. Pay particular attention to
the wiring and all connections between the generator terminal and the battery. In order to preserve
authenticity the regulator output (Battery) terminal is insulated in the exact same manner as the
original cutout and this terminal should be inspected regularly to make certain that the regulator
cover is not loose and in danger of shorting against the Battery terminal of the regulator. A 30 Amp
fuse placed in series with the generator battery wire at or near the battery end is a very good safety
measure for protection from shorts in the car and regulator wiring.
Important!! The correct generator should have only a single main generator terminal. If your
generator has 2 wires coming from it then you probably have a later V8 generator and will have to
use either a V8 regulator (12 volt version) or change your generator to the correct Model A type.
Note: All generators are not the same with regard to cutout mounting screw locations. Slight
bending of the regulator mounting feet may be necessary to line up the mounting holes of your
generator with the voltage regulator mounting foot slots.
Install the regulator in place of the cutout and make certain that both regulator mounting screws are
tight. Check that none of the screw heads on the bottom of the regulator are touching the generator
housing. Make certain that the main generator terminal is tight.
Connect the battery wire (car wiring) to the output (Battery) terminal of the regulator. You may notice
a momentary "spark" when the battery wire is first connected to the Battery terminal. The Ammeter
should not show any charge or discharge after the battery wire is connected.
Any reading on the Ammeter indicates that something is wrong and your voltage regulator
may already be damaged. Check all connections for shorts to the regulator cover or regulator
base.
D o n o t remove the voltage regulator cover as there are no user serviceable parts or
adjustments inside the voltage regulator.
Setting the generator third brush
A) Loosen the generator dust cover bolt and lift off the dust cover.
B) Loosen the third brush nut and shift the third brush assembly counterclockwise (as viewed from
the front of the car) as far as possible.
C) Start the car and bring the engine to a high speed that produces the maximum charge from the
generator. Turn on lights and observe an Ammeter reading of 3 to 5 Amps discharge.
D) Advance the third brush setting clockwise (as viewed from the front of the car) until the Ammeter
shows a slight charge of 1/2 to 1 Amp at this same high speed. The generator is now putting out 4
to 6 Amps. This should be the correct setting for the third brush. Do not advance the third brush
further or the setting will be too high! - The correct setting will occur with the third brush
advanced only slightly further than the center of its mechanical adjustment range. The third brush
must not be advanced further.
E) With engine still at high speed turn off lights and observe that the charge rate jumps to 4 to 6
Amps where the charge rate will remain until the battery reaches full charge. It may take a few
seconds, a few minutes, or a few hours for the battery to reach full charge. When the battery is
nearing full charge, the charging rate will taper off until only 1 to 2 Amps of charge current remain.
Make certain that the battery charge rate does not exceed 8 Amps during this charge time. A
lower setting of 5 to 6 Amps is best and will result in longer generator life. If charge rate is ever
allowed to exceed & Amps, generator damage will result. Do not attempt to readjust the third brush
once the regulator has begun to taper the charge since the regulator will tend to compensate for the
adjustment and it is very easy to advance the third brush too far which will result in generator or
voltage regulator failure.
F) Tighten the third brush nut.
G) Check proper operation by idling the engine with lights off and then quickly increasing engine
speed. The Ammeter should show a momentary high charge rate (4 to 6 Amps) then regulator
action should be observed by a noticeable decrease in charge rate.
H) Install the generator dust cover and tighten the dust cover bolt.
IMPORTANT! - A final check must.be made after 24 hours of no operation of car or battery by
starting the car with the starter and bringing the engine immediately to high speed. With all lights off
the Ammeter reading should be at or below & Amps. If higher than & Amps, reduce the third
brush setting immediately! This is the maximum reading you should ever see and it will soon
taper off once the battery comes up to charge. Thereafter the peak reading will be in the 4 to 6 Amp
range. This first reading is higher right after the car is first started because the battery voltage is
lowest since the battery has not been charged for 24 hours.

[JTT3]

Jeff FP had a 6 volt, 8 volt & 12 volt voltage regulator & if not mistaken all negative ground though I think John may have made a few positive grounds for A’s but I believe they were special occasions. Best John

Post Script- I’m so happy you are making your own designed voltage regulators! We need them.

[TRDxB2]

The 5055 is the Cut-Out & the 5055R is the Voltage Regulator
Instructions for the 5055R

5055R Inst.pdf

5055R heading.png

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Post a photo of the underside The Top is the Voltage Regulator, the bottom left is the FunProjects Cut-Out and the bottom right is one of the many versions of original cut-outs or reproductions

5055vr under.png

[AdminJeff]

The 5055 is the Cut-Out & the 5055R is the Voltage Regulator

I stand corrected. I missed the "R"!!