Overspeed governor calibration

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have a lift installation date 1974ish canadian origin maker Timberland Elliott, we have to retro fit a Holister Whitney safety gear and overspeed governor which are both American make, the lifts original speed is 49-55fpm the governor is set to electrically trip at 157fpm and mechanically at 171fpm the governor cannot be recalibrated any lower than 120fpm, have been informed by Holister Whitney that governor tripping speed is irrelevent to lift speed, do Americans live on this planet or make the rules up as they go along? on a serious note do we have to comply to EN81 as a British company in British waters installing the above, also the safety gear should also have a CE mark to enable it to be fitted in Europe?

Can anybody help answer this question and/or have any documentation/regulations on above

-- (liftgenie-liftgods@yahoo.com), February 25, 2005


According to the ASME Safety Code, section 218(ASME A17.1-2000), the maximum allowable tripping speed for a car speed of 125 fpm or less is 175 fpm. This makes perfect sense to me. Surely, a safety stop from that speed is not a concern.

Accordingly, it is standard practice (at least in the US) to set all governors to about 175 fpm trip speed for car speeds 125 fpm or less. And, therefore, there is no need to be able to set them for a lower tripping speed, though it may be possible to do so.

-- John Brannon (akaelevman@aol.com), February 25, 2005.

require more info

-- (iamthelift-genie@yahoo.com), February 26, 2005.

Please be specific.

-- John Brannon (akaelevman@aol.com), February 26, 2005.

Thankyou for replying i can understand the tripping speed as employed by the U.S. in the U.K. i am sure without going and digging the EN81 book out that overspeed governors have to electrically trip @ 15% above rated speed & mechanically @ 20% or 25% not sure without checking

and the other note is what regulations do i adhere to U.S. or U.K.

anybody any help as tried l.e.i.a. etc and just getting big old ru round

thanking you all in advance

P.S. also trying to build web site pls check & bear with me www.biguptheliftgenie@yahoo.co.uk

-- Lift Genie (bigupthelift-genie@yahoo.co.uk), February 26, 2005.

In the US, governors must trip at not less than 115% of rated speed, for speeds up to 2000 fpm. For speed above 2000 fpm, the maximum tripping speed shall not exceed 120% of the rated speed.

Further, they must trip at not more than the speed appearing in a table provided for the purpose (Table A section of this table is:

Rated Speed Maximum Gov. Trip Speed Max. Swt. Oper. 0-125 175 175 150 210 210 175 250 225 200 280 252 225 308 277

As you can see, speeds 125 fpm and below all use the same tripping and operating speed.When you consider that 125 fpm is 1.42 miles per hour, it is evident why this is the case.

Unfortunately, I cannot address the EN81 Code, but I'd suggest you look it up as I would think it surely contains similar provisions. The US is definitely on the same planet as Europe and what makes sense in one makes sense in the other.

Best Wishes!

-- John Brannon (akaelevman@aol.com), February 26, 2005.

EN81 The tripping speed of the governor shall accur at a speed at least equal to 115% of the rated speed of the lift and less than: 0.8 m/s for instantaneous safety gears 1.0 m/s for the captive roler type 1.5m/s for instantaneous type with buffered effect for progressive types 1.25v + 0.25/V = MAX TRIP SPEED MIN 115% OF RATED SPEED The electrical trip is 110% of rated speed 1m/s and above

-- bob (bob.morgan@blueyonder.co.uk), February 27, 2005.

Cheers Bob Thats all the speed regulations covered .however am desperate to find out what legislation i have to work to. As far as i'm concerned i am employed by a British Company so i have to work to EN81, the response from the client is that we work to the manufactures country of origin legislation which is U.S.A.

If the lift is U.S. origin but situated in British Waters Then to me this must be covered by EN81 regulations so therfore should it also have CE certification

thanks for all the assistance so far

-- (bigupthelift-genie@yahoo.co.uk), February 27, 2005.

Liftgenie, Try this this site http://www.dir.ca.gov/Title8/1604_19hmtl you might find what you need here.

-- Clark (pdell200@comcast.net), February 27, 2005.

If I read the data correctly as supplied by Bob Morgan, the governor must trip at a maximum of 157 fpm,assuming the safety gear is the instantaneous type. In your original posting, you indicated it could be adjusted to as low as 120 fpm. So, it would seem there is not a problem. Apparently, at speeds below roughly 200 fpm, the switch can operate at the same speed as the jaws grip and you indicate the switch currently operates at 157 fpm.

It seems totally logical to me that the equipment should comply with the regulations applicable in the place of installation and I assume that is EN81.

If the safety gear is any of the other types, there also appears to be no problem.

-- John Brannon (akaelevman@aol.com), February 27, 2005.

I would say that any work should be carried out to the british or european standards applicable althoughif this lift was installed in 1974 this lift was probably installed to BS 2655 and will certainly not be CE marked so a CE marked overspeed governor would not be necesary.it would however need to be tested and make sure that the safety gear and osg work as a compatible system eg pull through forces etc.

-- bob (bob.morgan@blueyonder.co.uk), February 28, 2005.

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