Active Output - Mettler Toledo IND500x Installationsanleitung

An example of how to wire to the active inputs is shown in the following figure.
Figure 33: Active Input Connections

2.5.4.2 Active Output

Using the Discrete I/O option with active outputs enables direct connection of low-power intrinsically safe
solenoids or piezo fluid control valves. The terminal provides the intrinsically safe voltage internally making the
output active and no external voltage is required by the external simple device. The source power is approxi-
mately12 VDC at a 50mA total current. All outputs operate from this single power source.
The IND500x Active Output option uses internal series resistors to limit the power to I.S. levels. These internal
resistors have the following effects on the Active / Active I/O option:
Increasing the current draw has an inverse effect on the voltage available to the control device.
The voltage will drop depending on the current required to operate the solenoid.
Estimates on available voltage based on current draw are shown in the table below.
Approximate Available Active Output Voltages
Current Draw
0 mA
10 mA
20 mA
30 mA
40 mA
50 mA
Any resulting lower voltages must be considered when selecting a control device. Consider the higher inrush
currents versus holding currents, which may have an influence on the possible switching times. Observe the
technical data and application notes of the respective control devices, provided by the manufacturer. Devices
from the following manufacturers that have been tested for correct operation with the IND500x and can be
connected directly to the outputs as shown are:
Hoerbiger S9: PS13950646A-00 and S29: PS13850646A-00 (ATEX approval only).
IND500x
SWITCHES
SWITCHES
SWITCHES
SWITCHES
SWITCHES
Available Voltage on Active Output
12.3 VDC
11.4 VDC
10.7 VDC
10.0 VDC
9.3 VDC
8.6 VDC
Installation​ ​ 33