Frequently Asked Questions
Question: Is a pullout switch a load break device?
Answer: Yes, pullout switches are evaluated and tested as load break switches. Make and break testing is required on circuits with currents at 100%, 150% and 600% of the nameplate rating. This testing is performed with dummy fuses installed in the pullout switch, since live fuses can open under these current levels.
Question: What standard is used for evaluating a pullout switch?
Answer: Initially, pullout switches were tested in accordance with UL98, Enclosed Switches, which is the standard used for testing most switches including safety switches. As the popularity of pullout switches grew and as UL98 evolved into a tri-national standard with Canada, Mexico and the United States, a unique standard called Pullout Switches, UL1429, was developed.
Question: Can a fusible pullout switch have dummy fuses installed?
Answer: Yes, there are circuits where fuses are not required, so dummy fuses can be mounted in the pullout switch.
Question: Can a pullout switch be used as a meter disconnect switch?
Answer: This is actually an excellent application for a pullout switch. A pullout switch can be installed ahead of a meter in accordance with NEC Article 230.82(3), to serve as a meter disconnect switch. The meter disconnect pullout switch usually has dummy fuses installed. A second identical pullout switch can be installed on the load side of the meter, which serves as the service disconnect. The service disconnect pullout switch would have fuses installed.
Question: Does operating a pullout switch present an arc flash hazard?
Answer: If a pullout switch is properly installed, properly maintained, and used in accordance with intent of UL1429, it is safe to operate without posing a hazard to the operator. After all, UL1429 is a “Standard for Safety”. When UL (or any NRTL) evaluates a product to this standard, they are certainly doing so with the safety of the person operating the device in mind.
Question: What is the difference between the terms “pullout switch”, “fuseholder” and “fuse block”?
Answer: A “pullout switch” is a product category as defined by UL. A pullout switch is investigated as a load break device. A “fuseholder” is also a product category (in fact, several product categories) as defined by UL. A fuseholder is merely a products that provide a means for mounting a fuse or fuses. A product Listed as a fuseholder is not a load break device. A “fuse block” is a slang term, which is often used when describing either a pullout switch or a fuseholder. Use of the term “fuse block” can be misleading, since it is not a product category. The best advice is to look at the Listing Mark on the product. If the product is Listed as a pullout switch, it will be investigated as a load break device. If it is Listed as a fuseholder, it is not a load break device.
Question: Can a pullout switch be mounted sideways?
Answer: Yes, pullout switches can be mounted vertically or horizontally. This is also true for Boltswitch Type 1/Type 3R cover kits, as described in Bulletin 133 & 134. Cover kits can be mounted vertically (hinge at the top) or horizontally.
Question: Do pullout switches have a line and load side?
Answer: No, a pullout switch can be fed from either the top or bottom as the fuses and blades are totally isolated when the head is removed. If it is not obvious when looking at an installation which end is the line end, it is recommended to mark “Line” and “Load” near the terminals.
Question: Can I use a pullout switch head with a different rating than the one that originally shipped with the base?
Answer: No, the catalog number marked on the pullout switch head must always match the catalog number marked on the pullout switch base.
Designed by Eric T. Maier