ZES ZIMMER LMG450, User Manual

Page: 69 / 306

Z E S ZIMMER Electronic Systems GmbH Chapter 4
69
The two functions are:
torque(Pn,fn,Un,In,pfn,pz,Rk,13,mk)
Calculates the torque in Nm. The
parameters are:
Pn: Nominal output power in W
fn: Nominal frequency in Hz
Un: Nominal line line voltage of the motor
in V
In: Nominal current in A
pfn: Nominal power factor
pz: Number of poles (twice the number of
pole pairs)
Rk: Stator line-line copper resistance in
Ω
mk No load torque correction
speed(Pn,nn,fn,Un,In,pfn,pz,Rk,13,mk)
Calculates the speed in min
-1
. The
parameters are:
Pn: Nominal output power in W
nn: Nominal speed in min
-1
fn: Nominal frequency in Hz
Un: Nominal line line voltage of the motor
in V
In: Nominal current in A
pfn: Nominal power factor
pz: Number of poles (twice the number of
pole pairs)
Rk: Stator line-line copper resistance in
Ω
mk No load torque correction
The copper resistance has to be measured at the same point, where the voltage is measured by
the LMG. The advantage is, that you can measure for example from a cabinet and that the
copper resistance of the wiring is included and by this eliminated from the calculation.
The results of
torque()
and
speed()
can be displayed in a user defined menu or transfered via
an interface.
A typical script could look like this:
# M-n-calculation
# Detailed motor description
# 2.2kW Motor DDA 90 L
# Input of the motor parameters
$cn=0.84; # Nominal powerfactor
$nn=2845; # Nominal speed 1/min
$pz=2; # Number of poles
# (2* pole pairs)