No power to write out or scan switch

[jukenorman]

Hi Rod,
Are you saying that the interlock trip coil energises when it should (when a selection pin is found) but the relay contacts don't flip over? And if you flip the contacts manually, the magazine motor stops? Back to page 40 then - check the contacts in the interlock trip relay circuit ie contact disc, A-B snap switch etc etc. You're probably not getting a solid enough pulse to the interlock trip coil because of poor contacts somewhere. Dirty contacts always have to be dealt with and the contact discs on Rock-Olas are well known for giving problems.

Norman.

[rockolarod]

Mar 3, 2021 21:51:46 GMT Ron Rich said:

Hi Rod,
Interesting-- What does the Service Manual say ?? Ron Rich

Hi Ron, it only shows sketches of the seperate units and I'm struggling to get my head around the written text.
 On the matter of different wiring sockets on the carousel motor (don't laugh), someone had put the connector block on the motor wiring round the wrong way. I was half way through putting a new connector block on when I realised. No wonder it wouldn't clip together. Had I realised before starting to fit the new terminals I would have been okay.
             Rod

[rockolarod]

Mar 3, 2021 22:22:13 GMT jukenorman said:

Hi Rod,
Are you saying that the interlock trip coil energises when it should (when a selection pin is found) but the relay contacts don't flip over? And if you flip the contacts manually, the magazine motor stops? Back to page 40 then - check the contacts in the interlock trip relay circuit ie contact disc, A-B snap switch etc etc. You're probably not getting a solid enough pulse to the interlock trip coil because of poor contacts somewhere. Dirty contacts always have to be dealt with and the contact discs on Rock-Olas are well known for giving problems.

Norman.

 Hi Norman,
           Trip coil seems to work correctly but that's as far as we get. My understanding(rightly or wrongly) is that the release coil should activate and create a short circuit that stops the carousel/read out carriage and switches power to the pick up arm and flips the selector lever back over.
     Rod
 

[Ron Rich]

Hi Rod,
I am at a dis-advantage here as I do not have a manual, and I am only using my memory-- Are you talking about the two relays located under the mech shelf in the box ? If so, my memory says there is a mechanical linkage between them-- when one gets a pulse, the pulse pulls the armature down, which mechanically releases the other armature. If so, is there a possibility that one of the armatures is "sticking" to the coil
Are ALL, the relay contacts making good contact-- adjusted correctly (see our FAQ's section)? Ron Rich

[jukenorman]

Yes Ron, you are correct about the interlock relay!

Rod I'm not sure if you are correct, are you maybe misinterpreting the drawings? Page 40 of the manual shows the magazine motor rotating at the point where a made selection pin is encountered. A circuit is made (heavy lines on schematic) through the trip coil of the interlock relay. This causes the interlock relay to change over. Page 41 of the schem-a-gram shows the state of the contacts of the flipped relay (note that they have changed state from page 40). An interlock relay contact (on the release relay side which has changed over to its de-energised position) presents a ground to both terminals of the magazine motor causing a dead stop (dynamic braking). The same contact of the interlock relay presents a ground to one side of the gripper motor enabling it to start.

Further on - on page 44, the gripper motor has completed placing a record on the turntable - cam switch 3 changes over energising the release coil of the interlock relay. The interlock relay contacts now flip back, dynamically braking the gripper motor. Other contacts may have also changed which I haven't covered.

The schem-a-grams show the state of play of the live circuits step by step. At the bottom of each schem-a-gram is a description of what is happening at that point - you need to study these descriptions carefully.  I apologise if I have confused things a bit - when the trip coil of the interlock relay pulls in, the release side of course moves to the other position and there are contacts on both sides.

Norman.

[Ron Rich]

Thanks Norman--- That's what my memory said-- but I have known it to lie,on occasion ! -- My guess is it may be magnetized, or the mechanical section is messing up--?? Ron Rich

[jukenorman]

Well Ron, I'm not so sure! I think it's more likely to be dirty contacts. The contacts rotating on the circular contact blocks on Rock-Olas are notorious for giving problems if not clean and properly adjusted. Bear in mind, the magazine motor is rotating so if the interlock trip coil doesn't get a pulse solid enough to flip the interlock element of the relay, the magazine motor won't stop.
Norman.

[Ron Rich]

Hi Norman,
I am having trouble recalling exactly how the mechanical lock worked on those-- Just seems to me that if the pulse is "strong enough" to pull one relay, that should be enough to release the mechanical lock, to the other one ? Ron Rich

[jukenorman]

Hi Ron
What you have are two relays sitting opposite each other with the armatures sitting vertically (as shown in the manual). Attached to each armature is a plate at an angle of about 30 degrees such that one plate sits above the other at the point of intersection holding the relay with the upper plate mechanically in the energised position. When the relay with the lower plate is energised, the two plates swap position and the other relay is now locked in the energised position - simple but effective!

I haven't been clear exactly what is happening in Rod's case. The trip relay sees only a pulse, I see from studying the circuit a bit more that a contact of the trip relay acts as a hold circuit - that contact would be a problem if it was dirty or badly adjusted. I have edited a post that I made earlier, I have decided that some of what I wrote might have been a bit misleading.

Norman.

[Ron Rich]

Hi Norman,
Yes-- that's what is sort of lingering in my memory-- that's why I can't understand how both relays can be "down" at the same time ( which is what I am understanding)?
Ron Rich

[rockolarod]

Hi Ron and Norman.

              Thank you so much for sticking with me on this.
 From what you are both saying and what I understand from the manual, when the trip coil activates the release coil should be released almost similtaneously.
 I think the next step is to remove the box and clean everything up on the bench(dining room table). As opposed to lying on the floor with a torch.
             Rod

[Ron Rich]

Hi Rod,
You know ?? THAT might just be a GOOD plan ! (BTW, for youz guyz, what don't speak "English, English", a "torch", is what we call a "flashlight" here in the USA) Ron Rich

[Ron Rich]

Rod,
Another thought -- If A-MP Mate N Lock version pins are used, check all of the female types. On the older versions of that pin, they tended to expand and loose good contact ! They also tended to "poke through" the backside, thus loosing contact totally, when the male was inserted. Ron Rich

[jukenorman]

Hi Rod,
I think that box removes fairly easily. Yes when the trip coil energises, the release relay should change over because it is only mechanically latched at that point. The trip coil gets a pulse when a selection pin is encountered, it is then held energised by one of its own contacts (important that is clean). When the release relay flips over, the trip coil de-energises through the contact that enables the dynamic braking but stays as is because it is now mechanically locked. All that happens in milliseconds of course!
Norman.

[Ron Rich]

Hi Rod,
If you don't know how to service the contacts, read the sticky in our FAQ's section -- Ron Rich