Safe State; Dangerous Failures; Specification (Extract); Diagnostic Times - HYDAC ELECTRONIC HLT 1000 Mode D'emploi

4.3.2 Safe state

The safe state is characterized by the output signal being permanently or cyclically
outside the range 4 ... 20 mA. The higher-level control system must recognise this
situation and put the machine (EUT) into a safe state.

4.3.3 Dangerous failures

A dangerous situation can arise if the linear position transducer of the higher-level
control signals an error position. The circuit and software design, diagnostic measures
and the choice of components all contribute to minimizing the probability of such
failures (see Point 9).

5 Specification (extract)

The full specification can be found in the user manual for the instrument.
5.1

Diagnostic times

Diagnostic time
Diagnostic interval
Process safety time
5.2

Electrical connection

Supply
Supply voltage (V
Residual ripple supply voltage
Power consumption
Electrical connection
(cable; 3-core)
Reverse polarity protection
Surge protection
Short-circuit protection
6
) nominal
in
Value
Continuous diagnostics
≤ 1000 ms
Value
9 ... 36 V DC
≤ 250 mV
< 2 W
Modification 000:
white: GND
green: 4 ... 20 mA signal output
brown: + U
B
Modification 100:
white: + U
B
green: 4 ... 20 mA signal output
brown: GND
Standard
Standard
Standard