Power Track system installation in Aircraft Hanger

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maghazadeh

Senior Member
Location
Campbell CA
Hello everyone,


I will be installing about 2000 ft of power track system in 4 rows of 500 ft long (manufactured by Vahle Mobile Electrification a German Company) 80 ft above floor powering sliding doors for the Aircraft hanger.

This track is rated at 100A, 600V, 3 phase, 3 wire w/GRD. Cat. No. KBHS 4/100-4. last number 4 means 4 meter long track section.
There will be (2) Two collectors per door installed in the power track sliding with the door, which second one used for redundancy and collector s1 and 2 cables connected to gather as one circuit.
Each collector is rated at 40A, 600V with 10 gauge or equal metric SO style cord (5 meter long), which within 8 to 10 ft goes into J box then conduit down to bottom of doors where motors/VFDs / controls are located.
Each door has two 5 HP, 480V, 3 ph motors, one on each end of sliding doors ( Total 8 doors. 4 on West side and 4 on the East side of bldg.).
There will be 16 total VFD's and controls.

Here is my questions that I like to get feed back from you guys.

1) Since track is rated 100A and collectors rated 40A each;
a) Is there a need for conductor over load protection means 75 to 80 ft up near top of doors? If the answer is yes then that will not be readily accessible.
b) Does 10 ft / 25 ft tap rule pretends to power track and collector? 100A bus is changing to 40A cable.
c) Is there any issue regarding parallel conductors since we use (2) collectors per circuit?
2) Building is a Aircraft Hanger. Does low voltage wiring (24V) needs to be in the raceway? All wiring will be above 18-to-24 inches AFF.

Thank you in advance for your reply.
 

Gregg Harris

Senior Member
Location
Virginia
Occupation
Electrical,HVAC, Technical Trainer
Hello everyone,


I will be installing about 2000 ft of power track system in 4 rows of 500 ft long (manufactured by Vahle Mobile Electrification a German Company) 80 ft above floor powering sliding doors for the Aircraft hanger.

This track is rated at 100A, 600V, 3 phase, 3 wire w/GRD. Cat. No. KBHS 4/100-4. last number 4 means 4 meter long track section.
There will be (2) Two collectors per door installed in the power track sliding with the door, which second one used for redundancy and collector s1 and 2 cables connected to gather as one circuit.
Each collector is rated at 40A, 600V with 10 gauge or equal metric SO style cord (5 meter long), which within 8 to 10 ft goes into J box then conduit down to bottom of doors where motors/VFDs / controls are located.
Each door has two 5 HP, 480V, 3 ph motors, one on each end of sliding doors ( Total 8 doors. 4 on West side and 4 on the East side of bldg.).
There will be 16 total VFD's and controls.

Here is my questions that I like to get feed back from you guys.

1) Since track is rated 100A and collectors rated 40A each;
a) Is there a need for conductor over load protection means 75 to 80 ft up near top of doors? If the answer is yes then that will not be readily accessible.
b) Does 10 ft / 25 ft tap rule pretends to power track and collector? 100A bus is changing to 40A cable.
c) Is there any issue regarding parallel conductors since we use (2) collectors per circuit?
2) Building is a Aircraft Hanger. Does low voltage wiring (24V) needs to be in the raceway? All wiring will be above 18-to-24 inches AFF.

Thank you in advance for your reply.

Is the hanger a classified location?
 

maghazadeh

Senior Member
Location
Campbell CA
Is the hanger a classified location?

I am not sure if it is a classified location or not. I have not seen any explosion proof devices. At one location there is a step down transformer which is about 18 inches off the finish floor.
All conduits are EMT and receptacles with standard 4 sq raised covers mounted at 48" AFF. there are several vending machine on the floor near exit door.
To me this building is similar to a car repair shop except they work on big jets.
 

Fishspark

Member
Location
Wisconsin
Occupation
Electrician
Hello everyone,


I will be installing about 2000 ft of power track system in 4 rows of 500 ft long (manufactured by Vahle Mobile Electrification a German Company) 80 ft above floor powering sliding doors for the Aircraft hanger.

This track is rated at 100A, 600V, 3 phase, 3 wire w/GRD. Cat. No. KBHS 4/100-4. last number 4 means 4 meter long track section.
There will be (2) Two collectors per door installed in the power track sliding with the door, which second one used for redundancy and collector s1 and 2 cables connected to gather as one circuit.
Each collector is rated at 40A, 600V with 10 gauge or equal metric SO style cord (5 meter long), which within 8 to 10 ft goes into J box then conduit down to bottom of doors where motors/VFDs / controls are located.
Each door has two 5 HP, 480V, 3 ph motors, one on each end of sliding doors ( Total 8 doors. 4 on West side and 4 on the East side of bldg.).
There will be 16 total VFD's and controls.

Here is my questions that I like to get feed back from you guys.

1) Since track is rated 100A and collectors rated 40A each;
a) Is there a need for conductor over load protection means 75 to 80 ft up near top of doors? If the answer is yes then that will not be readily accessible.
b) Does 10 ft / 25 ft tap rule pretends to power track and collector? 100A bus is changing to 40A cable.
c) Is there any issue regarding parallel conductors since we use (2) collectors per circuit?
2) Building is a Aircraft Hanger. Does low voltage wiring (24V) needs to be in the raceway? All wiring will be above 18-to-24 inches AFF.

Thank you in advance for your reply.


1a - you may be able to feed the100 amp conductor bar at 40 amps / or just feed it at 100 - the conductors from the collector shoes generaly end up in a fuse protected cabinet.
and without looking.. platform up there?
b - could be
c - no / thats used to insure a shoe from jumping out of the conductor bar over joints
2 - i dont think so

hope this helps - others im sure know too. - also contact the MFGR -
 

maghazadeh

Senior Member
Location
Campbell CA
Is the hanger a classified location?

Yes, it is classified location in certain area as per Article 513.

NEC 2008
240.21 (B)(4) Taps over 7.5 m (25 ft) Long.
Where the feeder is in a high bay manufacturing building over 11 m (35 ft) high at
walls and the installation complies with all the following
conditions:
(1) Conditions of maintenance and supervision ensure that only qualified persons service
the systems.
(2) The tap conductors are not over 7.5 m (25 ft) long horizontally and not over 30 m
(100 ft) total length.
(3) The ampacity of the tap conductors is not less than one-third the rating of the
overcurrent device protecting the feeder conductors.
(4) The tap conductors terminate at a single circuit breaker or a single set of fuses that
limit the load to the ampacity of the tap conductors. This single overcurrent device
shall be permitted to supply any number of additional overcurrent devices on its load
side.
(5) The tap conductors are protected from physical damage
by being enclosed in an approved raceway or by other approved means.
(6) The tap conductors are continuous from end-to-end and contain no splices.
(7) The tap conductors are sized 6 AWG copper or 4 AWG aluminum or larger.

(8) The tap conductors do not penetrate walls, floors, or ceilings.
(9) The tap is made no less than 9 m (30 ft) from the floor.

Well, since this install does not comply with condition # 6 and 7 above, then an overcurrent protective device is required.
By applying 10 ft or 25 ft tap rule 240.21(B)(1) and (2) an overcurrent device needs to be installed on the door at 55 ft min. AFF.
So, now how do I deal with accessablity for the overcurrent device at that height?
Only thing I can think of attaching a rope or chain to the handle of a 40A/3 CB just like plug in bus duct disconnect switch or installing a motorized CB.

Please chime in. Thank you
 

maghazadeh

Senior Member
Location
Campbell CA
Is the assembly of the powerai and the collector (100A/480V track and 40A/480V collector) consider to be a tap?
If it is, then installation must comply with one of the tap rule (10, 25, and or over 25 ft tap rule).
what would you do with accessibility issue of a OCP CB Installed at about 55-to 75 ft about finish floor which the only way to get to it is by using a boom left?

Please reply and give me your thoughts with code reference.
 

maghazadeh

Senior Member
Location
Campbell CA
1a - you may be able to feed the100 amp conductor bar at 40 amps / or just feed it at 100 - the conductors from the collector shoes generaly end up in a fuse protected cabinet. and without looking.. platform up there?

There is no OCP at the other end of collector's cable provided by the MFGR.

b - could be
c - no / thats used to insure a shoe from jumping out of the conductor bar over joints
2 - i dont think so

hope this helps - others im sure know too. - also contact the MFGR -

One of tap rule should apply here.
 
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