Plug Fuses & Box Cover Units

Plug Fuses

These fuses thread into fuse receptacles. Two types of threaded fuses are available: Edison Base (brass threads) and Rejection Base (porcelain threads). The two are not interchangeable. Two categories of plug fuses are available. The medium-duty fuses (TL or SL) have a time-delay feature for use on motor circuits. The heavy-duty fuses (T or S) are industrial strength products featuring the exclusive Cooper Bussmann dual-element construction. This spring loaded design provides superior short-circuit and overload protection. The T or S fuses have more time-delay than the medium-duty fuses in order to better protect motors and critical residential circuits. Plug fuses are rated for a maximum of 125Vac. TL and SL four pack (PK4) versions priced per box.

    Plug fuses are often used in residential and industrial branch circuit and motor protection. Fuses are used to protect furnace blower motors, pumps, power tools, garage door openers, etc. Motor protection fuses are usually used in conjunction with branch circuit protection. The fuse is often located in a box cover unit. Plug fuses provide a compact and inexpensive method to prevent damage to electrical motors. They help reduce downtime and lower maintenance costs by opening the circuit when a dangerous overload is present. When used for residential branch circuit protection, fuses are typically located in the main fuse panel.

Edison Base Plug Fuse

The base is the same as a light bulb base. All sizes fit the same fuse receptacle.

MB 125Vac Edison Base Circuit Breakers

MB 125Vac Edison Base Circuit Breakers

For replacing Edison base plug fuses in residential fuse panels.

 Part No. (Amps)  Poly Bag
 BP/MB-15  X
 BP/MB-20  X

Type T 125Vac Dual-Element, Time-Delay, Edison Base Plug Fuses

Type T 125Vac Dual-Element, Time-Delay, Edison Base Plug Fuses

Heavy-Duty Type T fuses for critical circuit protection. Used for air conditioners, furnace blower motors, swimming pool pumps, deep freezers or any circuit where motors frequently turn on and off. Use for all
commercial applications. The Type T plug fuse is an industrial strength product. It provides superior protection, yet will not open under repeated motor startups. Available in a wide amp range to permit exact sizing for motor protection.

 Part No.
 Blister Pack
 Poly Bag
 T-11/4
   
 T-16/10
   
 T-32/10
X
 
 T-4
   
 T-5
   
 T-61/4
X
X
 T-8
X
X
 T-10
X
X
 T-12
X
X
 T-15
X
X
 T-20
X
X
 T-25
X
X
 T-30
X
X

Type TL 125Vac Time-Delay Edison Base Plug Fuses

Type TL 125Vac Time-Delay Edison Base Plug Fuses

Medium-Duty Type TL fuses for residential motor circuits in kitchens, workshops, garages, utility rooms or any circuit with motors, relays or solenoids.

 Part No. (Amps)  Four Pack  Blister Pack
 TL-15 X X
 TL-20 X X
 TL-25 X X
 TL-30 X X

CSA Edison Base Plug Fuses

The base is the same as a light bulb base. All sizes fit the same fuse receptacle.

TC 125Vac Dual-Element Time-Delay Type D CSA Edison Base Plug Fuses

TC 125Vac Dual-Element Time-Delay Type D CSA Edison Base Plug Fuses

TC fuses for residential motor circuits in kitchens, workshops, garages, utility rooms or any circuit with motors, relays or solenoids.

 Part No. (Amps)  Four Pack  Blister Pack
 P-15 X X
 P-20 X X
 P-25 X X
 P-30 X X

P 125Vac Dual-Element One-Time Type P CSA Edison Base Plug Fuses

P 125Vac Dual-Element One-Time Type P CSA Edison Base Plug Fuses

P fuses for non-inductive loads such as lighting and heating circuits.

 Part No. (Amps)  Four Pack  Blister Pack
 P-15 X X
 P-20 X X
 P-25 X X
 P-30 X X

Rejection Base Plug Fuses

The rejection base threads prevent a larger amp fuse from being used. A 30 amp fuse cannot be installed in a 20 amp receptacle because of the different sized threads. Available in medium- and heavy-duty.

Type S 125Vac Dual-Element, Time-Delay, Rejection Base Plug Fuses

Type S 125Vac Dual-Element, Time-Delay, Rejection Base Plug Fuses

Heavy-Duty Type S fuses for critical circuit protection. Used for air conditioners, furnace blower motors, swimming pool pumps, deep freezers or any circuit where motors frequently turn on and off. Used for all commercial applications, the Type S rejection base plug fuse is an industrial strength product. It provides superior protection, yet will not open under repeated motor startups. Available in a wide amp range to permit exact sizing for motor protection.

 Part No.(Amps)  Blister Pack  Poly Bag
 S-11/4  X X
 S-16/10  X X
 S-2    
 S-21/2    
 S-32/10 X X
 S-31/2    
 S-4    
 S-5 X  
 S-61/4 X X
 S-7    
 S-8 X X
 S-10 X X
 S-12 X X
 S-15 X X
 S-20 X X
 S-25 X X
 S-30 X X

SL 125Vac Time-Delay, Rejection Base Plug Fuses

SL 125Vac Time-Delay, Rejection Base Plug Fuses

SL fuses for residential motor circuits in kitchens, workshops, garages, utility rooms or any circuit with motors, relays or solenoids.

 Part No. (Amps)  Four Pack  Blister Pack
 SL-15 X X
 SL-20 X X
 SL-25 X X
 SL-30 X X

SA Fustat Fuse Adapters for Using Type S and SL Rejection Plug Fuses In Edison Base Fuse Sockets

SA Fustat Fuse Adapters for Using Type S and SL Rejection Plug Fuses In Edison Base Fuse Sockets

The size-rejection SA inserts convert an Edison Base receptacle to accept the Rejection Base S and SL fuses. Once installed, the SA adapter can not easily be removed and limits the amp rating of the fuse that can be installed. SA adapters are available in a wide variety of sizes to protect motors and branch circuits. Use the chart to select the correct SA adapter. Ideal for retrofitting Edison Base fuse panels in rental property to prevent over-fusing and bring existing panels up to compliance with the NEC®.

 Amp Range  Part No.  Blister Pack  Poly Bag
 1 or less  SA-1    
 1.25 or less  SA-11/4    
 1.6 or less  SA-16/10   X
 3.5 to 6.25  SA-61/4   X
 7 to 15  SA-15 X X
 20  SA-20 X X
 20 to 30  SA-30 X X

Box Cover Units

For Supplemental Circuit and Small Motor Protection

 

Box cover units provide an efficient and economical method to protect motors from damage due to overloads. In most cases, the branch circuit protection in the main panel is not sufficient to protect small motors. For example: a motor rated for 6 1/4 amps will likely burn up before a 30 amp breaker will trip. The box cover unit permits a supplemental fuse to be installed. The fuse can be sized close to the motor load so that it opens when the motor draws current in excess of its amp rating, thus protectingthe motor from damage. Box cover units are available in a variety of sizes that fit standard electrical boxes. In addition to a fuse holder, many accessories make these units more convenient. When a switch is used (SS Series) it turns the fused power to the load on and off. The receptacle (SR Series) allows motors to be plugged into the fused circuit. All box cover units are UL Listed for a maximum 15 amp fuse at 125Vac (except as noted).

  Part No.   Blister Pack   Reload  Poly Bag   Maximum Hp/Volts/Amps   Box Type   Description
 SOU X    3/4 Hp / 125Vac / 15A  21/4” Handy  Fuse Holder Only
 SRU X X  1/2 Hp / 125Vac / 15A  21/4” Handy  Fuse Holder Plus Receptacle
 SSN      1/2 Hp / 125Vac / 15A  Single Gang  Weatherproof Fuse Holder and Switch
 SSU X X  1/2 Hp / 125Vac / 15A  21/4” Handy  Fuse Holder Plus Switch
 SSY X X  1/2 Hp / 125Vac / 15A  4” Square  Fuse Holder Plus Switch
 STY**      1/2 Hp / 125Vac / 15A  4” Square  Twin Fuses Plus Double Pole Switch

** Double pole switch opens both sides of the circuit. Can be used for two separate motors with common switch or a single motor (3/4Hp, 250Vac max.)

SSU/ SRU

Box Cover Units

SSN Weatherproof Model

SSN Weatherproof Model

SOU & SRU

SOU & SRU- Box Cover Units

SSY & SSU

SSU & SSY- Box Cover Units

STY

STY- Box Cover Unit