Chapter Two Installation
man_905-105_2.16 Page 23
2.4.6 Pulse Input (905-1)
For the ”-1” module, digital input 1 may be configured as a pulse input (max rate 100 Hz, min. off
time 5 ms). In this mode, both the pulse rate and the pulse count are available for mapping to a remote
output. The pulse rate may appear at any analog output on the remote unit, while the pulse count can
appear at a Pulse Output on another ”-1” or Digital/Pulse Output on a ”-3” or “-4” unit. The pulse input
should be connected in the same way as a digital input.
Active pulse signals can be connected directly provided the peak voltage is between 3.5–13V and the
low voltage is less than 1.5V. Note that the 905U will ground the negative of the pulse signal. If the
voltages are not compatible, use a solid state relay to isolate the two devices.
2.4.7 Pulse Inputs (905-2 and 905-4)
For the ”-2” and ”-4” modules, the four digital inputs (DI 1-4) may be configured as pulse inputs. The
first digital/pulse input DI 1 has a maximum rate of 1000 Hz (min. off time 0.5 ms), while DI 2-4
have a maximum rate of 100 Hz (min. off time 5 ms). When using DI 1 at high pulse rates (more than
100 Hz), a divide by 10 function may be configured to reduce the pulse count at the output, as Pulse
Outputs have a maximum rate of 100 Hz.
For each pulse input, both the pulse rate and the pulse count are available for mapping to a remote
output. The pulse rate may appear at any analog output on the remote unit, while the pulse count can
appear at a Pulse Output. The default update time for pulse counts is 1 minute. This can be changed
by changing the update time configuration - refer Chapter 4 Configuration for further details. The
pulse count is a 16 bit value - “roll over” of the count when it exceeds the maximum value is
automatically handled by the modules.
To Next Page
Loading...
