ZENER 8000-V Installation Manual
IM00165
61
NEMA
[The American] National Electrical Manufacturer’s Association, publishers of
various NEMA standards.
PF
Power factor. The ratio of real (active or in-phase) current to the total current in
an AC circuit.
PID
A type of automatic controller that seeks to drive a measured value (e.g.
temperature, pressure etc) to a preset value by means of a control effort (e.g.
motor speed) determined by proportional, integral, and derivative functions.
PID, reverse acting A PID control system in which an increase in control effort
(e.g. motor speed) results in a decrease in the measures variable (e.g.
temperature). A common example is a cooling tower where an increase in fan
speed causes a reduction in water temperature.
Ramp
A control function within the ZENER 8000-V that controls the rate at which the
motor speed can increase or decrease.
Remote
Operation of the ZENER 8000-V via connections made to the control board
terminal strip.
RMS
Technically, Root-Mean-Square. A method of measuring an AC voltage or current
that gives the same numerical result as a DC voltage or current would on the
basis of heating effect.
RMS line current
AC input current measured in a way that reflects the true heating value of the
current.
SCN
The terminal on the ZENER 8000-V for the connection of the screen of all cabled
associated with analogue and digital control functions.
UL
Underwriters Laboratories Inc. An American organization involved in product
safety standards and certification.
Variable Torque
A load characteristic in which the driving torque requirement is significantly
influenced by speed. This term is most often used to describe the load
characteristic of centrifugal fans and pumps.
VRef
A reference voltage (5.0V) available on the ZENER 8000-V control terminal strip
to assist in generating a speed reference voltage etc.
