hi mate. what safety is tripping?

These are the safeties under the car. These elevators require actual car safeties because they are roped hydros. There is no direct connection between the piston and the car frame. We will be installing battery lowering devices to these elevators but during the testing you have to shut off the power and let it the elevator return to the lowest floor. If you shut off the power in flight it trips the safeties every time. This happens on all the cars. We're trying different things to solve this problem but overall this safety design is pretty much CRAP!

What's Northern have to say about it?

(I mean, other than the boiler plate "We have no problems" stuff)

Still waiting for a call back.

hi mate.we install a spanish hydrolic which are all roped hydrolics. in fact i would say its old technolgy to dig the caison and ram into the ground these days. from memory the safety's under the car are the safety gear(bc its roped) and the slack rope switch(underneath the terminating rope plate).the safety gear will have an arm where the overspeed gov rope attaches and sometimes this is too wobbly. the bar that runs from front to back that joins both sides of the gear is generally square. the gov rope arm that i said before has a spring set on the 2 side of the square bar and sets the tension of actuation. we have found you need to tighten these up or else just stopping the lift will trip these.a good guide of tension should be if you grab the gov rope it requires a really good tug on it to actuate the movement.also too the weights on the gov idler wheel in the pit can to heavy as well, we have lightened these also. also is your stopping speed too quick via the hydro block. this may be a fault as well.finally be VERY careful with the auto relevel/lowering with battery power as we tend to disconnect it here as it maywell cut mechanics in half when working on them ie if your working on the lift and constantly switching the lift on and off. cheers mate let me know how you go.

uppo72, You mention that battery lowering is commonly disconnected, for safety.

Here in California, we have an auxillary contact inside the mainline disconnect. When you turn the 3 phase power off at the disconnect, the auxillarly contact opens, and the battery lowering is disabled.

This contact is also sometimes connected in series with a contact that represents the actuation of the shunt trip circuit breaker, (the one feeding the disconnect), so that if the power is turned off for a definite purpose, such as the actuation of a heat detector, or if someone wants to work on it, and turns it off at the disconnect, in either case, the battery lowering will be disabled.

Is this not how it's done in Melbourne?

hi vic. some manufacturers have the lowering thru the main breaker but our spanish supplier doesnt.im on service so i dont get to make the decision on what should have been installed but since we dont really have rules regarding emergency lowering they just disconnect the battery supply. unfortunately in victoria(melb)our industry was deregulated in the late 90's ie the dept of labour and industry is no longer there so we are self regulating. this means that although there is a australian standard (which is high)frankly companies just tend to do what they want within reason. we can also follow the en81 regs as well.we have nowhere near the oversight that you guys do ie yearly inspections from o/speed to escalator step movement.come to think of it we didnt have yearly inspections only contruction and modernisation inspections, which we very detailed(ie they made you blow fuses on every lock) but unless a situation came up that was it. i read about your inspectors and laugh about what you have to go thru. all of us reckon that it will take 1 major accident to maybe change all that.just recently a kone mechanic was hurt badly on construction when he rode what we think was a near completed new lift. what we understand happen was the lift still had the locks shorted, while the car doors where damaged so they had been removed. but to test the lift the car door contact and the landing door locks where shorted and they tested the lift like this. BUT this guy forgot about this and turned lift on normal service from exclusive and when he walked out of the lift it took off and smacked him on the head and jaw. the upshot was a broken neck, busted jaw and a whole lot of grief by his workmates. very sorry story all round. the guy is ok now not sure if hes back at work yet.hopefully worksafe(worker comp) will institute some action.when we heard about this we could understand why anyone would run alift like this. madness.

Wow, interesting. Thanks for the information.

We are absolutely paranoid about leaving either the safety circuit, or door locks jumped out. There is even talk about using "time out" jumpers, that open internally, after a preset time elapses.

yep you and me both mate.whenever i short out 1 lock i still go and find the lift and check the landing doors. just paranoid about hurting someone which is a good thing i think.

Yep...

Admin- Are these knurled safety shoes, that dig in when they contact the rail?

Does the car frame have roller guides?

I know the CEMCO residential roped hydros have eccentric roller guides, so you can adjust the distance from the safety knurls to the rail. If I was doing it, I'd want to know what kind of clearance the safety shoes have between them and the rails, and also, can this distance be adjusted.

These are wedge type safeties with really no adjustment that can be made as far as I can tell. I'm curious to see what Northern will say when I get a hold of their engineer. We just recently picked up this job and I know the old company had a lot of issues with nuisance safety trips. We added a spring to hold tension on the actuating rod which prevented nuisance tripping on deceleration. However, it still trips on power off or a door pick when the car is moving.
I was hoping that someone out there had been through this before with Northern. I'll be sure to post the fix if I hear from Northern.

Yeah, I'd be really interested to hear about this one...thx..

admin im pretty sure theres no real adjustment via the safety gear. you adjust the slipper/roller guides to suit then probably shim the gear. as i said earlier its more likely the actuating arm is moving too much via the governor rope. is this the same for this manufacturer? for the spanish stuff we use its a simple fix. or is the gear coming in Not via a gov rope actuation. simple to prove just remove the gov rope from the actuating arm. we have found this alot and is a pain in the arse. we have slipper guides and you have to recentre the guides so you have about a 1mm gap clearance on the gear. remember if there is too much weight on the gov idler wheel then on change over of speed the arm jerks which will cause the gear to come in.

I think some Otis safety shoes had little "hold down" springs on top, that tended to keep them from moving vertically, unless the linkage was actuated. If the linkage was actuated, the springs would then just compress, as the shoes slid up into the wedge.

Maybe something like that (shoe springs) would help in this case.