You might search for aluminum service drop triplex with messenger, or something similar. Also look for "messenger support clamps" for pole attachments. Pretty sure Hubbell has something like this.
Waross - Can you please advise why are you suggesting reevaluating the plant distribution method & voltage? Let me explain the specific situation.
Utility is providing primary service at 15KV, I am planning a Padmounted transformer 1500KVA, 15KV/480-277V with Outdoor Padmounted 480V Switchboard to provide power to 3 Process load centers each aproximately 100 to 400 Ft away from this Low voltage switchboard. The site has large part of it covered with concerete which client wants to leave undisturbed for future use. So I figured 480V aerial bundled cable supported from poles would be the lease expensive choice for power distribution to the load center for this process plant. Cable bus or underground ductbank will be the most expensive choices.
1500 KVA @ 480 Volts = 1800 Amps
= 600 Amps per panel.
#2/0 aluminum conductor neutral supported cable\quadruplex\90 deg. is good for 305 Amps.
Two runs per load center, separated- not bundled, will handle your loads.
Voltage drop calculations are your responsibility)
When you asked for bundled conductors I visualized much higher amperages.
-------------------- Ohm's law
Not just a good idea; It's the LAW!
Thanks for your calc I did understand that part. Reason for my question is Okonite markets this aerial bundled cable 600V (and above) but haven't run into use of it for aerial outdoor power distribution in-plants or by utilities for residential power distribution except at point of service drop connection. Therefore asking for you learned colleague's feedback if this is accepted practice in US or only in developing countries.
Fun with numbers, based on:
Table 36A
Maximum allowable ampacity for aluminum
conductor neutral supported cable.
Three AWG sizes doubles or halves the cable cross sectional area.
Configurations with equal total cross section or weight of aluminum.
90 deg 4/0 305 Amps x 2 cables = 610 Amps
90 deg 1/0 200 Amps x 4 cables = 800 Amps
90 deg #3 x 8 cables
90 deg #6 85 Amps x 16 cables = 1380 Amps
You can see the law of diminishing returns kicking in here.
I would probably look at 2 x #4/0 AWG or 3 x 1/0 AWG and do a comparative take-off on the support hardware and labour.
1/0 = 106 mcm x 3 = 318 MCM total area. 600 Amps
4/0 = 212 mcm x 2 = 318 MCM total area.- 610 Amps
500 mcm x 1 = 500 MCM total area.- 555 Amps
600 mcm x 1 = 600 MCM total area.- 615 Amps
By using a one conductor per phase bundle, you are using 600 MCM/318 MCM = 1.89 or 189% of the aluminum that would be required for three parallel runs.
Bigger is not always better.
Your choice.
Voltage drop calculations may make a difference and indicate fewer, larger cables.
-------------------- Ohm's law
Not just a good idea; It's the LAW!
