1. You may use a higher voltage rated fuse anywhere a lower voltage fuse is used, as long as the current rating is the same. THUS, the Handbook statement that you can use a 1 Amp. 250 Volt fuse in a low voltage (e.g. 12 Volt) circuit in place of a 1 Amp. 32 volt fuse. The current rating of a fuse is for AC OR DC.
Consequently, how many amps is a 250v fuse?
Fuses are rated in amps. Most fuses for household items are 250V. We are told that we can use 250V fuses of the same amperage rating for our nominal 120V circuits. Thus, if I need a 5 amp fuse for an amplifier I get a 250V 5 amp fuse.
Can I use a fuse with a lower amp?
Replacing a fuse with a lower value one, however, is not unsafe but may cause problems if the load current is higher than the fuse value. It is thus generally recommended to replace it with a fuse of the same value. However, in some cases, it is probably okay to use a fuse with a lower value.
What is the voltage rating of a fuse?
The voltage rating of a fuse must be at least equal to or greater than the circuit voltage. It can be higher but never lower. For instance, a 600V fuse can be used in a 208V circuit. The voltage rating of a fuse is a function of its capability to open a circuit under an overcurrent condition.
Can I use a 250v fuse in place of a 125v?
You can never apply a fuse whose max voltage rating is smaller than the application voltage. You can replace a 125V fuse with a 250V fuse of equal amperage as long as the application voltage is 250V or less. You can not replace a 250V fuse with a 125V fuse of equal amperage if the application voltage exceeds the 125V.
How fuse rating is calculated?
Fuse rating = (watts/volts) x 1.25
Note the power of the appliance – usually in the appliance manual,
Note the voltage (240 volts in the UK).
Use the next highest fuse rating after the calculation. Say the calculated fuse rating is 2.2679 amps, use a 3 amp fuse.
What is a fuse rating?
A fuse rating is the current need to blow (break) the fuse. When a fuse has blown it removes electrical power from an electrical circuit. The fuse rating is usually on the side of the fuse. Thefuse rating is usually defined in ‘amps’ – amps are the unit of measurement of electrical current.
How does a fuse work?
The fuse breaks the circuit if a fault in an appliance causes too much current flow. This protects the wiring and the appliance if something goes wrong. The fuse contains a piece of wire that melts easily. If the current going through the fuse is too great, the wire heats up until it melts and breaks the circuit.
What is the current rating?
Also described as current rating or current-carrying capacity, ampacity is the RMS electric current which a device or conductor can continuously carry while remaining within its temperature rating. The ampacity of a conductor depends on: its insulation temperature rating; ambient temperature.
What is the meaning of fusing factor?
75; The rewireable fuses have fusing factors of approximately 1. Therefore, fusing factor minimum current or rating of fuse 17 nov 2015 a. Power system operation and protection google books result. ), definition of word fusing factor (elec. It is the ratio of minimum fusing current to rating fuse.
What is minimum fusing current?
Fuse wire, it is also defined earlier. Minimum Fusing Current: It is minimum value of current due to which fuse melts. Current Rating of Fuse: It is maximum value of current due to which fuse does not get melt. Fusing Factor: This is the ratio of minimum fusing current and current rating of fuse.
What is the meaning of cut off current?
In electronics, cut-off is a state of negligible conduction that is a property of several types of electronic components when a control parameter (that usually is a well-defined voltage or electric current, but could also be an incident light intensity or a magnetic field), is lowered or increased past a value (the
Why VBE is 0.7 V?
For an unbiased transistor, considering only the BE junction which is a pn junction diode, 0.7V is the potential barrier. In an npn transistor base is positive(p) and emitter is negative(n). So the potential barrier vbe=0.7V. But in a pnp transistor the base is negative(n) and emitter is positive(p) so the vbe=-0.7V.
What is the cut in voltage?
There is a definite forward voltage at which the diode starts to conduct significantly. This is called the knee voltage or cut-in voltage and is equal to the barrier potential of the p-n junction.
What is the difference between knee voltage and breakdown voltage?
The forward voltage at which the current through the PN junction starts increasing rapidly is known as knee voltage.It is also called as cut-in –voltage or threshold voltage. Breakdown voltage: The reverse voltage at which the PN junction breakdown occurs is called as breakdown voltage.
What is the cut in voltage of Ge and Si diodes?
A silicon diode has a voltage drop of approximately 0.7V, while a germanium diode has a voltage drop of approximately 0.3V. Though germanium diodes are better in the area of forward voltage drop, silicon diodes are cheaper to produce and have higher breakdown voltages and current capabilities.
Do LEDS have a polarity?
Diode and LED Polarity. Diodes only allow current to flow in one direction, and they’re always polarized. A diode has two terminals. The positive side is called the anode, and the negative one is called the cathode.
How does a pn junction diode acts as a switch?
A diode conducts (offers 0 resistance ideally i.e., it acts as a short circuit) only when it is forward biased so there will be current flow in the circuit and it offers very high impedance ( it acts as a open circuit) when reverse biased so there will be no current flow. This way p-n junction diode work as a switch.
Can a diode be used as a switch?
Diodes can switch analog signals. A reverse biased diode appears to be an open circuit. A forward biased diode is a low resistance conductor. The only problem is isolating the AC signal being switched from the DC control signal.
Why a pn junction is called a diode?
As the name indicates a diode has two terminals. These are referred to as the anode and cathode. When in circuit, the current flow (conventional current flow) is across the PN junction diode from the anode to the cathode. As the diode is a one way device, current is inhibited from flowing in the other direction.
When a diode is reverse biased?
Connecting the p-type region to the negative terminal of the battery and the n-type region to the positive terminal corresponds to reverse bias. If a diode is reverse-biased, the voltage at the cathode is comparatively higher than at the anode. Therefore, very little current will flow until the diode breaks down.
When a pn junction is forward biased?
Forward Biased PN Junction Diode. When a diode is connected in a Forward Bias condition, a negative voltage is applied to the N-type material and a positive voltage is applied to the P-type material. If this external voltage becomes greater than the value of the potential barrier, approx.
What happens when PN junction is forward biased?
When the p-n junction is forward biased, the electrons move from the negative battery terminal to the positive battery terminal. The electrons and holes do not diffuse/combine together and disappear! When the p-n junction is reverse biased, the barrier resistance is increased, so little or no electron current flows.
What is the peak inverse voltage?
Definition. Peak Inverse Voltage (PIV) or Peak Reverse Voltage (PRV) refer to the maximum voltage a diode or other device can withstand in the reverse-biased direction before breakdown. Also may be called Reverse Breakdown Voltage.