Square D hammers are some of the most popular hammers on the market today and have been for many years. Commercial Square D switches use a complicated numbering scheme that can be very helpful to understand. These methods apply to both new and used switches.

First, we’ll look at a common Square D part number that is available as a new or used switch, the Square D KA36200.

Frame Type: what

Interrupt: IN

termination:-

Number of poles: 3

volts:6 (600)

Amps: 200

Suffix: –

As you can see in this example, the part number KA36200 means it is a Type K frame, standard break, 3 pole, 600 volt, 200 amp. These types of switches generally come in several different varieties, most commonly with different amperage ratings. A 300 amp breaker would be numbered KA36300.

Square D offers many types of frames. The frame type determines the size, shape, and style of the breaker. The interrupt has several options. A=Standard, C=Extra Tall, I=Current Limited, Y=Standard (F frame only). Terminal options are None = Line I, F = No Terminals, L = Terminals on both ends, P = Terminals off end.

The suffix offers many options:

F=Frame Only

G = ground fault

DC=500VDC

M = molded case switch

MT = Top Feed Lugs

V=View window

By understanding this numbering scheme, you can figure out the part on any Square D breaker. If you have a KA36070, but need to install a 100 amp, you should order a KA36100.

For residential switches, the Square D QO frame type is the most popular. Square D switches are available at home improvement stores and online. Many online stores also sell used Square D hammers. These used breakers are viable options when an electrician is unable to purchase a replacement breaker through traditional electrical stores. When a homeowner is faced with replacing a residential circuit breaker, most of the time a replacement can be found at a local hardware or electrical supplier.

If you are replacing a Square D breaker and need a breaker with a suffix, your only option may be to purchase one directly through Square D. Many of these breakers are in the class of custom order breakers and are only available from Square. D, and are often made to order if not available from stock in a warehouse.

Square D has long been a pioneer in new and used hammers. In 1951, they released the first plug-in style switch, a style that is still in use today. In 1991, Square D was bought by a French company, Schneider Electric. Schneider Electric continues to use the Square D name for all switches in the US market. Although Square D is now owned by a different company, their product quality and availability is second to none.

Square D switches are available at almost all home improvement stores, hardware stores, and online switch vendors. Many hammer suppliers offer new and used Square D hammers. Some stores specialize in used and obsolete Square D switches.