4
ELECTRICAL CONNECTIONS
42
SITRANS FX330
www.siemens.com/flow
05/2016 - A5E36751269-AA
4.3.6 Pulse output / Frequency output
The maximum frequency of both pulse output and frequency output is 1000 Hz.
The connection is made between terminal M2/4 Common (-) and M1 for Hi Current (+) or M3
NAMUR (+). Only one of the two connections M1 or M3 can be selected in menu C2.2. The output
is selected as pulse or frequency output in menu C2.2. The output is a passive "open collector"
output which is electrically separated from the current interface and the flow sensor. It requires
its own power supply
2
. The total resistance must be adapted so that the total current I
tot
does
not exceed 120 mA.
For selection of measurement variable and adjustable data of the pulse or frequency output
refer to chapter "Menu description C - Setup", menu "C2.2.2 Pulse Output" or menu "C2.2.3
Frequency Output" and appropriate submenus.
Figure 4-5: Electrical connection pulse output
1
Signal converter power supply
2
Pulse output power supply
3
Pulse counter or frequency meter
Figure 4-6: Pulse output signal definition
1
T
max
2
Closed
3
Open
4
Pulse width
≥
0.5 ms
INFORMATION!
Make sure the pulse width is in line with the pulse rate.