When to specify manholes versus handholes?

[josephacarter]

I'm working on a Federal Government project. I've reviewed the UFC's and NEC. I can not find anything about what wire size or # of parallel feeders that "triggers" the use of a manhole instead of a handhole.

My application is 4 SETS of (4) 500KCMIL, (1) #3/0G, in 4"C, with (2) SPARE 4"C, concrete encased duct bank. No splices! It's a 450' feeder that has a 45 degree bend, then a 270 degree bend. The design calls for a hand hole at each bend. My project manager is telling me they have to be manholes.

NEC 314.30 size of the handhole directs you to NEC 314.28 which refers to "#4AWG or larger" which in my case #500's are larger.
UFC 3-550-01 EXTERIOR ELECTRICAL POWER DISTRIBUTION says "handholes can be sued for low-voltage" which applies; and "Do not use handholes for splicing shielded power cables" which does not apply.

The design is a year old and by a different engineer no longer with the company, nor reachable.

If there is any "rule of thumb" or "industry standard" telling me a manhole is the proper application, I'll change the design. Else, I don't see an issue with the design.

Any input would be greatly appreciated!

Thanks,

Joe

 

[Another C10]

I never really thought about it till now, but as I look and the terms hand hole cover compared to man hole cover I'd presume its self explanatory,

The hand hole enclosure would probably be shallow , a small accessible underground pull box to simply get your "Hands" into possibly traffic rated as well, The man hole is probably more of a underground vault with a ladder allowing the persons entire self to literally go below the surface to work within the concrete encased enclosure.

 

[don_resqcapt19]

This a design issue, but typical hand holes would be small for that application.

I would use a manhole with built in rigging points for the pulling process.

What is a 270° bend? Typically bends are 90 degrees or less.

Also based on what you posted, I would be looking at a single handhole or manhole. I might even run a pulling calculation and decide that no manholes are needed. Every time you use a pull point for the conductor installation you increase the risk of damaging the conductors.

 

[Julius Right]

The maximum depth for a hand hole: less than 2 ft

No steel conduit for high and medium voltage cable is recommended.

See NEC Table 300.5 Minimum Cover Requirements, 0 to 1000 Volts, Nominal, Burial in Millimeters (Inches).

It is not recommended for medium and high voltage cable.

See attached recommendation of USA Departments of the Army and the Air Force Technical Manual for Electric Power Supply and Distribution

 

[Carultch]

Is there a term that works generically to indicate either a manhole or handhole, when leaving it unspecified as to which one it actually is?

In the same way that OCPD works as a generic term for fuses and breakers, when the application doesn't care which one is used.

 

[don_resqcapt19]

The maximum depth for a hand hole: less than 2 ft

No steel conduit for high and medium voltage cable is recommended.

See NEC Table 300.5 Minimum Cover Requirements, 0 to 1000 Volts, Nominal, Burial in Millimeters (Inches).

It is not recommended for medium and high voltage cable.

See attached recommendation of USA Departments of the Army and the Air Force Technical Manual for Electric Power Supply and Distribution

What limits a hand hole to a depth of 2' or less? Many of the Quazite boxes 30" x 48" or smaller are listed as hand holes and are available in depths to 36" . They have other enclosures that I would consider as hand holes, because of the open bottom construction up to 48x72x48.