Resistor Terms:
'A', 'B', 'C', 'D/E', 'F-L', 'M', 'N', 'O', 'P', 'R', 'S', 'T', 'V-Z'
Variable Resistor Schematic Symbol
Variable Resistor: A resistor that is not fixed in value. A resistor that may change its value. Also called a Potentiometer, Trimmer, or Rheostat. Companies that Manufacturer Variable Resistors
Variable Resistor
Varistor: A resistor that changes value with applied voltage. A varistor may also be called a VDR [Voltage Dependent Resistor]. Varistors will have a negative voltage coefficient. Companies that Manufacturer Varistors
Varistor Symbol
Vendor: A company that sells or Manufacturers Resistors.
Vertical Mount Resistor: A type of resistor package that mounts standing up, all leads on one end. A bracket may also be used to secure the resistor into the PWB, leading to the term Bracket Mount. Bracket Mount resistors would be used for high shock and vibration applications.
Voltage Rating: Resistors shall have a rated direct current (dc) continuous working voltage or an approximate sine-wave root-mean-square (rms) alternating current (ac) continuous working voltage at commercial-line frequency and waveform corresponding to the power rating, as determined from the following formula:
Water-cooled Resistor: A high wattage resistor that uses water to cool the device. The water flows via pipes within the resistor to draw heat away from the device.
Adjustable Wirewound
Wirewound: A Resistor made up of resistance wire, wound on an insulated form. A wirewound resistor may be variable or fixed. Wire-wound resistors are normally used as power resistors. Types of Wirewound Resistors; Heat-Sinked, Phenlic, Ceramic, Flameproof, Enamel, and Silicone Coated.
Note the graphic above depicts an RX33 style Adjustable Wirewound Resistor from MIL-R-19365.
WireWound Resistor Cut-Away View
Zero-Ohm Resistor: [Jumper Resistor]. A resistor with a value of zero ohms. Zero-Ohm Resistors are used as interconnect points on a PWB. They may also be used to tie two circuit points together while in system test so an internal trace may be accessed but removed in the final application, removing the physical test point. When array of Zero-Ohm Resistors are used in a single package the term Jumper Chip Array may be used. The term Zero-Ohm Resistor is some what of a misnomer in that they will tend to have the same tolerance as any other value in the same package style, so there may be a value attached to a Zero-Ohm Resistor.
