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: k
Interrupt: HAS
termination:-
Number of poles: 3
volts: 6 (600)
amps: 200
Suffix: –
As you can see from this example, the part number KA36200 means it is a Type K Frame, Standard Break, 3 Pole, 600 Volt, 200 Amp. These types of breakers generally come in several different varieties, most commonly with different amperage ratings. A 300 amp circuit breaker would be numbered KA36300.
Square D offers many types of frames. The type of frame determines the size, shape, and style of the breaker. The interrupt has several options. A=Standard, C=Extra High, 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=500 VDC
M = molded case circuit breaker
MT = top feed lugs
V=View Window
By understanding this numbering scheme, you can figure out the part on any Square D switch. 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 stores. Many online stores also sell used Square D hammers. These used circuit breakers are viable options when an electrician is unable to purchase a replacement circuit 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 fall into the custom order class of 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 purchased 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 most home improvement stores, hardware stores, and online switch providers. Many hammer suppliers offer new and used Square D hammers. Some stores specialize in used and obsolete Square D switches.