Hello I have recently acquired a Protosound 1 unit that I would like to install in a 2242 New Haven F3 set. I was going to polarize the motor and use it directly with the Protosound unit but didn't know if the voltage drop would hinder the engine performance. Has anyone done this type of upgrade?
Thanks
Mark
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what do you mean by polarized the motor mean? are you referring to the polarity of the dc feeding the motor?
Alan
If you run the motor field winding through a full wave bridge rectifier the ac motor will act like a d.c. motor responding to polarity changes. you do lose some voltage doing this. I saw the procedure referred to this Name in a book several years ago.
My only concern would be if the Protosound board had the ability to supply all the current needed for the open frame motors.
-Horizontal or vertical motor?
I reread your post more carefully. Since it is only a single motor, you should be OK. You might want to put the capacitors across the brushes to limit some of the electrical noise. Add a one microfarad, non-polarized capacitor, between each brush and ground.
Thanks for the suggestion on the caps. Now that you say it the original QSI ACRU units had you doing the same thing. I seem to recall that 2 of the diodes on the protosound unit are strictly for dropping voltage. Do you know if this is the case?
Mark
Before you install the PS/QSI, hard wire the loco in one direction with the field(or brushes) powered by a full wave bridge, connected in series to the other, and try running it with DC to see what the performance will be like.
Thanks for the suggestion on the caps. Now that you say it the original QSI ACRU units had you doing the same thing. I seem to recall that 2 of the diodes on the protosound unit are strictly for dropping voltage. Do you know if this is the case?
Mark
There are several voltage drops. Input AC goes through FWBR, than the + output goes through 2 common diodes an one FWD diode for FWD + voltage so a FWBR and 3 diodes before it gets to the relay/
If this is a ACRU no need for rectifying.
I run a MPC single motor Pullmore off a 103 electronic reverse unit with a bridge. Lowered top speed, but no issue with the starter set e-unit handling the current in one pullmore. G
I used to run all my post war F-3s with DC. A big (25 amp) Full wave BR right on the transformer wired with reversing switch and full wave BR in each engine. The engines ran really well , Especially (lash-ups) . They never got of a sink. Horns were disconnected.
Then came along QSI with their small electronic E-unit, and also the DCRU and ACRU.
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