Ferraz Shawmut:
Products with a Story
CONFIDENTIAL
Cable Limiters
UL Listed for Code Compliance
Increase System Reliability and Versatility with
Ferraz Shawmut Cable Limiters
Reminders & Questions:
Did you know? Cable Limiters do
not provide overload protection.
They are designed for short circuit
protection only.
CP Cable Limiters are designed for the protection of low voltage distribution networks, feeders and service entrance cables. Provide short circuit
protection to multiple cable runs consisting of three or more conductors
in parallel per phase or single cable runs where more than one customer
is connected to one transformer.
Did you know? All cable limiters can
be ordered with heat shrink tubing
providing water-proof protection to
the limiter body. Just add –HS to
the end of the part number.
Did you know? Cable Limiters are
not selected by ampere rating.
Cable Limiters are selected by
cable size. The NEC Article 310
defines the ampacity of conductors
based on size and cable limiters are
designed accordingly.
Are cable limiters required by
code? Not by the NEC. NEC Article
230.82(1) permits the use of cable
limiters. Contact your local utility
for local code requirements.
Does Ferraz Shawmut have a UL
Listed product? YES, Ferraz Shawmut cable limiters have been UL
Listed since 2006. Ask for UL File
number E305297.
Can’t find what you are
looking for or having trouble
selecting the right product?
Call Ferraz Shawmut Technical
Services at (978) 465-4853.
Cable Limiters are most commonly installed in underground power distribution systems found in industrial, commercial and residential applications. The limiters are designed for use in both radial and network type
underground systems to reduce the cost of installation and maintenance.
Install cable limiters on the 600V secondary network to prevent thermal
damage caused by fault currents up to 200,000 amps.
Features
Ferraz Shawmut cable limiters are available for cable sizes 2AWG up to 1000kcmil. All cable limiters can
safely interrupt faults up to 200kA and are rated for 250VAC or 600VAC. Seven terminal variations are available
utilizing tube (Cable), offset blade (Bolt-on), straight blade (Bolt-on) and compression rod (Mole) terminations.
Ferraz Shawmut 600VAC rated Amp-Trap® CP Cable Limiters are UL Listed. Installation and tooling information
is available online.
Application Example:
1. Three or more conductors in parallel per phase
The most common application for cable limiters is found in commercial or industrial applications where
parallel cables are used on service entrances and feeders. Install one limiter on each end of each cable
run to isolate faulty conductors in case of insulation breakdown, splicing or any unforeseen short circuit
incidents. Safeguard your multiple cable runs by isolating one faulty conductor and allowing the remaining
cables to keep the system up and running. Generally, at the customer’s expense, the utility will supply and
install cable limiters on the utility equipment and the electrical contractor will install the cable limiters at
the customer’s equipment.
2. Single conductors where more than one customer is connected to one transformer
It is also common to see utilities install cable limiters where more than one customer is connected
to a single transformer. The reason being is if one customer experiences problems in the main service
equipment, the cable limiter on that service will open, isolating the problem from the other customers
sharing the same transformer. This is most common for multiunit apartment buildings, condominiums,
and shopping centers or strip malls.
Requirements for Selecting the Proper Cable Limiter
1) Cable Size (#2 AWG through 1000kcmil)
2) Required Terminations (Seven variations available)
3) Cable Material (Cu or Al)
us.ferrazshawmut.com
ST-CP-1/2008