Glossary Terms
Terms that are used on the Manufacturing Automation website
z-axis
The third dimension in a graphics image. The width is the x-axis and the height is the y-axis.
ZCL instruction
Zone-control last-state instruction. A user-programmed fence for ZCL zones.
ZCL zones
Assigned program areas that may control the same outputs through separate rungs, at different times. Each ZCL zone is bound and controlled by ZCL instructions. If all ZCL zones are disabled, the outputs in the zones would remain in their most recent controlled state.
Zener diode
A diode that, above a certain reverse voltage (the zener value), has a sudden rise in current. The voltage across the diode remains essentially constant for any further increase in reverse current, up to the allowable dissipation rating.
Zero Adjustments
Used when ‘setting up’ a transducer to adjust the output signal to zero when zero load/pressure is applied.
Zero Balance
The output signal of the transducer with rated excitation and with no-load applied, usually expressed as a percent of rated output.
Zero Offset
1. The difference expressed in degrees between true zero and an indication given by a measuring instrument. 2. See Zero Suppression
Zero Point
The electrical zero point where zero millivolts would be displayed. Used in conjunction with the slope control to provide a narrower range calibration.
Zero Power Resistance
The resistance of a thermistor or RTD element with no power being dissipated.
Zero Return
The difference in zero balance measured immediately before rated load application of specified duration and measured after removal of the load, and when the output has stabilized.
Zero Suppression
The span of an indicator or chart recorder may be offset from zero (zero suppressed) such that neither limit of the span will be zero. For example, a temperature recorder which records a 100? span from 400? to 500? is said to have 400? zero suppression.
Zero Voltage Switching
The making or breaking of circuit timed such that the transition occurs when the voltage wave form crosses zero voltage; typically only found in solid state switching devices.
ZIF connector
Zero-REPLACEion-Force connector. A connector for which male and female contacts do not initially touch each other while the connector halves are being engaged. Instead, the halves are physically positioned together, and then a turn of an actuating cam arrangement mates all the contacts at once.
