suspended transformer

[electrofelon]

The anchors are already engineered. Not sure what the engineer would really do. I don't see that shielding you from any liability as you are still responsible for installing them properly. If you are worried about liability, you should just decline the mechanical work altogether.

 

[jumper]

I also find as I get older I worry much more about what could happen.

Yep.

 

[infinity]

That totally depends on all the other factors. Many times there is no upside, other times there is. Given the table there is so very little risk of pull out that the liability is minimal. I am assuming you don't get engineering approval to install a conduit rack for example, or to secure a motor starter to a wall. I fully understand your concern, I just think it is no likely to be and issue.

I'm with you. I see electricians install conduit racks without giving the weight of the conduit, hardware and conductors any thought.
In many cases the weight hanging on a two rod rack exceeds that of an 800 pound transformer hanging on four rods.

 

[Strathead]

I'ts the design professional's duty to provide sufficient detail to build it. It's not your fault they failed to provide the detail. If you never ask, they're going to keep doing it to you.
And the EE very well may already have standard details. Engineers are allowed to cross into other disciplines which they are proficient in. I'd think an EE is proficient in hanging a tranny, especially if he wrote the spec.

That actually presents another argument against asking. I rarely see an engineer who doesn't over-engineer things, Send it to the Engineer and he is going to have you run strut spanning 20 feet and rods, cross-braces, gold plated strut, silver plated hardware. If he didn't spec it out then I am fully capable of installing it with say 3/8 rod that has all the design factors needed. if he doesn't like it, I will be glad to change it for a nominal service charge.

 

[mgookin]

I could see isolation dampers for vibration to keep noise out of the structure and to extend the life of the connection to the concrete. Maybe it would take strut and rod to do that.
Do you make more money if it's a $100 extra or if it's a $400 extra?

 

[Saturn_Europa]

If the OP does decide that his staff will tackle the problem, how long is liability assumed? For the warranty period only? If the concrete anchors are rated for the load and installed in accordance with manufactures recommendations can they be held liable in the event of a failure 5 years from install? How about 10 years?

 

[mgookin]

If the OP does decide that his staff will tackle the problem, how long is liability assumed? For the warranty period only? If the concrete anchors are rated for the load and installed in accordance with manufactures recommendations can they be held liable in the event of a failure 5 years from install? How about 10 years?

Being the listing is for hanging fire sprinklers it could be a long time.

 

[iwire]

If the OP does decide that his staff will tackle the problem, how long is liability assumed? For the warranty period only? If the concrete anchors are rated for the load and installed in accordance with manufactures recommendations can they be held liable in the event of a failure 5 years from install? How about 10 years?

I would say as long as the company is in business it code be held responsible

 

[JoeyD74]

I would say as long as the company is in business it code be held responsible

Im sure there is a lawyer out there who would try to go after you no matter how long it's been,
that could be said about everything we do though and in the end it's our job to install the equipment properly.
I would have no issue hanging a transformer like that as long as the concrete was sound.

 

[infinity]

Im sure there is a lawyer out there who would try to go after you no matter how long it's been,
that could be said about everything we do though and in the end it's our job to install the equipment properly.
I would have no issue hanging a transformer like that as long as the concrete was sound.

If you had a poured concrete building I would assume that the concrete was pretty sound since it's holding up the entire structure. For an old building with something like cinder fill I wouldn't be relying on anchors to hold up much weight although we recently did a job where an anchor combined with epoxy held up to about 3000 pounds before the cinder fill concrete failed when tested.

 

[MBLES]

its a 45 kva transformer. unfortunately there is not detail on print. we will find out more details during site walk this week.

 

[Saturn_Europa]

its a 45 kva transformer. unfortunately there is not detail on print. we will find out more details during site walk this week.

Interesting topic. Please post back when you guys make a decision.

 

[Ingenieur]

I am with you and for the doubters

https://www.us.hilti.com/medias/sys...chnical_information_ASSET_DOC_LOC_1543428.pdf

is a link to the pullout strength of Hilti anchors, you could easily use even 4- 1/4" anchors in only 2000 PSI concrete, and still mount a 2000 pound transformer with a safety factor of 4.

I would use 3/8 without hesitation and 1/2" would be the overkill you may want to use if you have a cautious customer who wants to pay.

This
a 3/8 even in lw concrete on pan in the thin section is 500 lb w/sf of 4
evdn with the worse adj factor 250 lb
2 pieces of strut with 3 3/8 each
no problem for 1000 lb

 

[iwire]

This
a 3/8 even in lw concrete on pan in the thin section is 500 lb w/sf of 4
evdn with the worse adj factor 250 lb
2 pieces of strut with 3 3/8 each
no problem for 1000 lb

What is your plan for sesimic protection?

 

[Ingenieur]

I'm 'the engineer'
my response, the contractor is responsible for means and methods
submit your proposed method and I will review

 

[Ingenieur]

What is your plan for sesimic protection?

With a sf of 6 x 500 / 200 x 4 = 60 not too concerned

 

[iwire]

I'm 'the engineer'
my response, the contractor is responsible for means and methods
submit your proposed method and I will review

It's not my problem, you the engineer said to hang it and what methods to use but you did not provide any seismic protection. It's on you. :thumbsup:

 

[iwire]

With a sf of 6 x 500 / 200 x 4 = 60 not too concerned

:lol:

 

[Ingenieur]

It's not my problem, you the engineer said to hang it and what methods to use but you did not provide any seismic protection. It's on you. :thumbsup:

I did not state the methods
that contractually the contractors scope 'means and methods'

Transfomer weighs 350
hardware 50
lf 1.4
use 600 lb
4000 fc'
3/8 good for 920
6 bolts
6 x 920/600 x 4 x 1.4 = 50 sf

my concern would be having you megger the wire you pulled

 

[jumper]

It's not my problem, you the engineer said to hang it and what methods to use but you did not provide any seismic protection. It's on you. :thumbsup:

Yep.

Sorry Iggy but the specs, all of them, fall on the EE if requested.