I found an old box of Atlas switch machine switches, selectors and a controller tucked away for over 15 years in a closet. Is there a way to use a multimeter (I have) to check if they are still electrically operable?
Cedarwoodron
After all that time some tarnish will have built up on the contact surfaces inside which are not accessable for cleaning. You can use a meter to check for continuity but since those switch controllers and selectors are not that reliable they should be replaced with regular pushbuttons and toggles.
I have used some that were over 30 years old and had been over 25 years since used last, I have had no problems. They may have a little tarnish on them, but I never had contact problems. If they have serious corrosion on them, that could be another matter.
Good luck,
Richard
Yes, you can use a miltimeter to check them and see if they are still usable. Even the cheap $2.99 digital VOM from Harbor Freight is good enough for this.
Set the meter to the "continuity" setting if it has one (generates a tone when shorted). If your meter does not have the continuity setting, you can use the Resistance setting with its range at 10K or higher. Even the diode test setting on the Harbor Freight meter can be used.
Touch the probes together and the meter should show you what it is going to read if a switch is usable. My meter changes from "1." to "0.01" Then touch the probes to the switch you want to test and see if you get the same or very close readings when the switch is activated.
If the meter reading doesn't change, the swtich is defective or badly corroded and should not be used.
Make sure your meter has a good battery or every switch will read as defective.
Unless they are rusted/corroded, chances are they are fine. I've had some of mine since the 1970s, and only a small percentage have failed since that time.
IMO, the easy test is using two leads, a bulb and a battery to check the continuity between the various terminals and switch positions.
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
Even if you don't want to use them for control of your trains. You could always use the selectors, for your building lighting and on off control of accessories. They would all be able to control on/off functions.
Take Care!
Frank
any of them can be taken apart and cleaned. I've done it.
Mike C.
The knock on the switch machine controllers is that they sometimes stick in the ON position. They are supposed to be momentary contact. When this happens, you will be sending constant current through your switch machine coils.
If you have a capacitive discharge (CD) circuit, it will limit the current and you should be OK.
If you don't have one, you will learn the smell of a frying switch machine coil.
It takes an iron man to play with a toy iron horse.
Where is the OP?
I have had the Atlas switch's stick but my CDS protected the motors. I just pushed down on the switch and pushed it back an forth a couple times,all was good then.
Have a good day.
Lee