I have an MRVF controller that has been upgraded numerous times. Unfortunately those "upgrades" were not transferred to the print. I have chased out the safety string on the back plane of the relay panel. Lately i am getting an open safety string due to a picked SPR relay. This relay also has a dip switch timer. Without taking the couple of days neccessary to trace all of the legs attached to this relay and its contacts, i don't know what it is for. I am thinking maybe it is a stall protect timer or something. Does anyone have an updated print, or knowledge of the purpose of this circuit? Thanks.

-- Jim Bass (ollieagain@hotmail.com), November 16, 2004

Answers

Been a long time since I worked on one of them also. I think that timer starts when you approach the floor. Is your car leveling real slow? Those units had bad traction problems with one of the machines they used. If the approach into the floor is good swap out the timer. I have had those artisan timers get screwy on me before. They are relatively inexpensive so what the heck. Sorry I couldnt be more help. Work Safe. One more thing you could check the countdown on the approach on one of those boards and if it is to slow just bump it up. Just a hexadecimal value. I beleive there is a way to set up a short floor run also. Not sure though.

-- fixalift (fixalift@yahoo.com), November 16, 2004.

As I remember, and it's also been a long time, if the door interlocks don't make up when the car is trying to leave the floor, it also times SP.

-- Richard Orr (rorr503@msn.com), November 16, 2004.

Thanks for all the responses. I will check into it further tomorrow. I am leaning towards replacing the timer. I was having slow leveling before, but i sped up the car speed and shortened the stopping distance. I have had lots of problems with this car. Even with a new load weighing device, a new load weighing board, adjusting the load weighing per the Otis tip, i still can't get the car to level the same in both directions. I had slowed the car down and shortened the stopping distances to get the car to come into the floor in both directions on both single floor and multi-floor runs. It worked for a while, but then the SPR started flipping out. Now i sped it back up and let it relevel a little bit and the SPR still comes in. THanks again for all the advice. Glad to know i was on the right track.

-- Jim Bass (fixingelevators@sbcglobal.net), November 16, 2004.

If any of you are interested, I got some info from Otis yesterday on this problem. The Spr fault is triggered, on a timer, if the car does not sense rotation through either of the directional rotation relays (uro/dro) but the BIH timer relay is picked indicating that the brake may still be picked. In other words, the elevator thinks that it is stalled. The SPR timer starts during the time that the car has stopped and the directions fall out, but the BIH relay is still picked by the timer. The BIH timer is only set for 2-3 seconds so this SPR should almost never pick, as the SPR timer is about 50 seconds. But, if there is alot of releveling in the car, the BIH relay might not have time to reset before it is picked again when the car goes to move. This is what i have found so far. Made some adjustments this morning and the car is still running so far.

-- Jim B (fixingelevators@sbcglobal.net), November 23, 2004.