Outputs and Digital Input
Specifications
VT400 Technical Manual, Rev. A5
49
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UM-VT400-EN
7 Outputs and Digital Input
The VT400 is able to interface with weighing automation systems, using two
optoisolated outputs (digital setpoints) and one digital input. There is also an analog
output configuration.
The digital outputs (setpoints) are triggered when the scale reads an upper
weight threshold, defined by the user. There is a separate threshold for each
setpoint.
The analog output configuration consists of a galvanically-isolated D/A converter,
generating either voltage or current output. Relevant parameters can be modified
using the
A-CAL
dialog (see section
7.4).
The digital input is used as a tilt switch. When a signal is received on the input
cable, the display locks for a certain period of time.
7.1 Specifications
7.1.1
Digital Outputs
Transistor output open collector positive common.
24VDC + 10% / 100mA per output.
Max off: State voltage 30VDC / leakage 100µA.
Optoisolated to 2.5KV.
Short-circuit protected.
2ms maximum delay for both on and off positions.
7.1.2
Analog Outputs
Galvanically-isolated D/A converter.
Circuit may be operated as current output or voltage output.
Output is capable of driving 20mA into 1K
Ω
load.
Current output values: 0-20mA, 4-20mA, 0-24mA.
Voltage output values: 0-10V.
Powered by an external 24VDC, Main instrument PSU can be used.
7.1.3
Digital Input (Tilt Switch)
9-24VDC, positive common optoisolated to 2.5KV.
Input resistance 3.3K
Ω
.
2ms maximum delay for both on and off positions.