1The voltage rating of a fuse must always get greater than or equal to what?
The supplied voltage
2Which rating on a fuse relates to its ability to revent an arc from restriking across the opened fuse element after a fuse has blown?
The voltage rating
3A basic rule of thumb for selecting a fuse for a normal application is to select the fuse at what percentage of the full load current of the application?
125%
4What is the difference between an overload and a short circuit as related to fuses?
Overloads melt out the fuse link in one place, a short opens the link in multiple places
5Motor circuits require what type of fuses?
Time delaye
6The starting current of a motor can be how much greater than the normal full load current?
5 to 6 times
7Since a short circuit can cause so much physical damage, what aspect of a fuse's design is critical, if a short circuit should occur?
Current limting rating
8 What is the advantage of a current limiting fuse?
Can open the circuit before the first peak voltage
9In a single element fuse, what happens indside the fuse if an overload condition occurs?
A link melts out
10In a single element fuse, what happens inside the fuse if a short circuit occurs?
The link melts out in multiple locations
11In a dual element time delay fuse, what happens inside the fuse if an overload occurs?
Fusible pin melts out
12In a dual element fuse, what happens inside the fuse if a short circuit occurs?
THe ends also melt out so the link is opened in multiple locations
13How does a "rejection" type fuse differ from a standard fuse?
Cannot replace it with a larger fuse beyond the fuse holder rating
14A rejection type just can only be replaced by a fuse having the same what?
Voltage, physical sized, and similar amp rating
15Why do we find so many specialty small physical sized fuses used in the commercial foodservice equipment industry?
UL codes requiring more juses in a machine today that take up physical space
16It is important that all possible causes for a blown fuse be carefully checked in equipment using small specialty fuses because of what characteristic of most of these type fuses?
They are very expensive
17Type AGC fuses are what type of fuse, fast blow or time delay?
Fast blow
18Type ABC are what type of fuse, fast blow or time delay?
Fast blow
19Type SC fuses rated at 5 amps or lass what whay type of fuse?
Fast blow
20Type SC fuses rated at 6 amps and above are what type of fuses?
Time delay
21Type SC fuses rated at 20 amps and above are what type of fuse?
Time delay
22Type KTK and KTKR are what type of fuse, fast blow or time delay?
Fast blow
23What is the rejection feature that is built into SC fuses?
Length of the fuse
24Type JJN and JJS are what type of fuses?
Fast blow
25When replacing a main fuse, what kind of fuse should always be used, and why?
Time delay
26How many different sized screws cap type fuseholders are there for SC type fuses?
3
27What will happen if you installation 6 amps SC fuse in a 15 amp fuseholder?
It will work fine, this holder works for .5 to 15 amp fuses
28What will happen if you install a 15 amp SC fuse in a 30 amp fuseholder?
It will fit loosely and have intermittent contact
29What will happen if you install a 30 amp fuse into a 15 amp fuseholder?
You cannot, it is to long
30If a fuse continuously blows, how do you narrow down the problem?
Ammeter on the line to find out if the problem is a short circuit or overload
31Can fuses just fail due to old age?
Yes
32If a fuse blows often, could it just be that the wrong type of fuse is being used?
Yes
33Can a problem with the camps in a fuse panel cause a fuse to blow?
Yes, if they are loose
34How can you tell if a problem exists with the spring loaded contact clamps in a fuse holder?
Turn the power on for a few minutes, then turn it off and check the fuses. If they are hot, then the clamps are oose and the fuse older or disconnect needs to be replaced
35What kind of problem can occur from carbon build up around a fuseholder?
Arcing, and short circuit to ground
36What questions will you need to answer to select the proper fuse for an application that you want to fuse?
Fast blow or time delay. Voltage rating. Current rating.