Loud E-unit why?

[andregg1]

Hi
Somebody know the diference between the F3- 2343 and GP-2338 E- unit because both still working perfect, but the GP is very very loud insted the F3 E-unit is so quit doesn't make noise.
thaks guys!!
Andre.
by the way I'm agree with the "question of week" or something like that, because we need to keep all technical data in one place. may be is time to start.
A.

[lionelsoni]

I doubt that there is any systematic difference between the two models. Individual e-units are very idiosyncratic about noisiness.

There have been postings about quieting e-units. Some say replace mechanical ones with electronic. My favorite solution is to convert the AC coil voltage to DC with a small bridge rectifier. If this does not completely quiet the unit, you can add capacitance at the coil to reduce the ripple in the DC. But you have to keep in mind that, as you reduce ripple, the coil's power dissipation increases, requiring at some point that you, for example, add series resistance to keep the coil current at a safe level.

[trigtrax]

An e-unit is a coil in a steel structure. While running your trains the coil is always energized with 60 hertz. E-units are held together by cinched steel tabs in slots. If the mechanical connection are loose the steel vibrates.
Your F3 has the e-unit fastened to a die-cast frame where the geep uses a sheet metal one. The sheet metal will amplify any e-unit vibrations more that the diecast.

I have always liked a "loud" e-unit buzz as I consider it part of the charm of toy trains.. but if you can't get the noise to your own levels by tightening the e-unit then you might want to consider one of the electronic replacements

[andregg1]

So I can use foam between the e-unit and the bracket?
of course that I keep the e-unit grounded.

[lionelsoni]

You could even use nylon screws, as long as you jumper the ground connection around them.

I suspect that most of the noise comes from the armature inside the coil. If the pieces of the frame are vibrating against each other, you could probably find out by touching the joints while it is buzzing.

[daan]

My e-units always make a loud buzz, but that's because I have 50 Hz out of the wall socket. i don't know if rectifying can harm the coil, since a coil designed for AC normally runs hot on DC, but I can be wrong here, never tried it myself..

[Frank53]

I have a 621 switcher that has an e-unit so loud it vibrated a filling out of my teeth.

I have had it in for repair a couple of times, but anything over 9 volts makes it buzz like a sonofagun.

It's been in the shop for a couple of weeks and the owner was going to switch it out with one that came in from a garage sale.

Have to check on that tomorrow.

[3railguy]

The biggest noise culprit in a mechanical reverse units is loose staked or rivited joints. check it to make sure it is solid and peen any stakes that seem loose. The rivet that holds the lever in place likes to work loose too. That is not as easy to peen as the stakes. An easy method is to shim it with a thin half washer which you can make by cutting off the end of an open (two finger) electrical connector. Also check that the drum is not too loose. You can adjust this by sqeezing the E unit body. Don't squeeze too hard. it might slap you.

[andregg1]

50 hrz was my problem too but I got the solution.
230 volt ac 50 hrz go to transformer that change to 12 volt dc 25 amp
and I use another transformes is a power supply for camping is for a car.
so this transformes give me 110 60hrz.
good luck
Andre.

QUOTE: Originally posted by daan

My e-units always make a loud buzz, but that's because I have 50 Hz out of the wall socket. i don't know if rectifying can harm the coil, since a coil designed for AC normally runs hot on DC, but I can be wrong here, never tried it myself..