Table of Contents
Advertisement
4.3.
Digital input (PWM)
The PWM digital input can be used to receive information
on the percentage (%) of power to be supplied to the load
(see the Configuration and Programming Manual for digital
input configuration).
The signal can be generated by an external controller or
external PLC via digital outputs (logic output for Gefran
instruments).
This is achieved by alternating the status of the output in
ON for time TON with the output in OFF for time TOFF. The
sum of TON+TOFF is constant and is called Cycle Time.
Cycle Time = TON+TOFF
The power level is given by the ratio TON/Cycle Time and is
normally expressed in %.
1
2
3
INDIG1 PWM IN
4
5
6
7
GND
8
Figure 28 - Example of external controller connection
81900A "MHW_GPC-40/600A"_03-2021_ENG_page 79
The GPC's INDIG1 digital input automatically adapts to the
cycle time from 0.03 Hz to 100 Hz and obtains the power
percentage level (%) to be supplied to the load from the
ratio TON/(TON+TOFF).
NOTE: For INDIG2 and INDIG3 inputs, the maximum PWM
frequency is limited to 1 Hz. INDIG4, however, is not config-
urable as a PWM input.
Connection example
In the following connection example, the Gefran 650 instru-
ment controls the temperature and sends the control signal
from the D type logic output (Out2) to the DIG1 input of
GPC-M.
The cycle time is 0.1seconds.
+24V
Controller
Logic Output
Type "D"
Advertisement
Table of Contents
