Westinghouse Hydro Duplex 1964-1965 era. 7 stops. Type ES relays (piano key relays). Car calls == car only responds to 1st and 7th floor calls in the up direction. After going to 7th floor, stepping/notching resets then answers car calls perfectly in the down direction. Will not answer correctly in the up direction until it sees terminal floor at 7, then it answers those up calls in the down direction that were already logged or any new ones. PI reads 1, 3, nothing, nothing, nothing and then 7 on the way up. It answers 3 most of the time (for whatever reason). ONce in a while hoistway dispatching is OK because the PI reads 1,2,3,4,5,6, and then 7. It responds correcty, unequivocally, in up direction after shut off for 30 minutes or so. When something heats up after a while, car starts to act up again. Seems that notching or stepping causing the problem...but NA and NB are opening and closing correctly and reading correctly. Coils are giving right coil reading even when messing up.

That circuit can be confusing. You should have a back contact of 39A I believe to start you. Check that guy and check that none of the relays are residually holding in. Also check that relays are not "halfpicking" while energized! You will also have 81U&81D relays for direction in circuits. Also check your power supply to be sure your outputting enough for the relays. You are losing selector right away. I doubt it's tape switches, more likely on the controller and since it's directional look at 81U's. Another good one is cold solders on back of relays? Have still found cold solders 40 years later! Timing is everything in these circuits!

Like halfpick said, timing, relay contacts, cold solders... If NA and NB are working that means AL and BL from the hatch tape box are driving the selector properly. If it's directional, I'd be looking at 85U or 82U and/or 81U, 81UA, 81UAB etc.. Always check for voltage first then look at the relays for a) are they functioning? b) halfpicking? c) residual? d) plenty of pad on the contacts? e) armature leaf spring broken? f) contact out of the ladder? Look at the S0 and SA0s also..

Selector switches replaced --- AL and UL. 82 U replaced and car is still doing same thing after it heats up a little. We left and the car was fine for 2 days.......we thought we had it. Any more information would help.

Monte,
Just had a trouble with a 2BC 3 stop. What I found was the 39 relay gap was too small not allowing the relay contacts to make & brake properly. Also look close and make sure the contacts are seated in the phenolic ladders.

jkh -- will do and let you know. Thanks so much. Once again, we thought we had it...ran good for 4 days.

Does this unit have ES or SR relays?

E-man

ES relays.

THanks.

Have you checked the controller for half picking relays?

Like E-Man and I've both said...check relays...I have seen the brass screw worn enough to hold a relay from doing it's job! At the Big "S" we replaced them with Stainless Steel Screws! Contact pads are another good one to look at!

Thanks so much. NB Auxiliary relay was bad --- replaced it completely. You were right it wasn't picking all the way. THe problem was it was SOMETIMES. When it was cool, it was fine......leave it shut off for an hour or so. Sometimes it ran for days straight.

we replaced the whole relay and got it. Thanks so much.

Now you know why his name is halfpick??? You can check for that easily and take 30 seconds and install a half picking relay shim and a Teflon shim. Take your needle nose or baby channel locks and put it on the armature screw nut and watch the relay function. If it's gonna half pick it will show up then. Check all the relays in the controller... saves headaches.

E-Man

Thanks.!! that is what we will do. You were right, that is what it was doing -- picking sometimes (all the way), half-picking other times.

You are correct E-Man! I bleed circle W blue!