Limiter

The limiter allows the electrical output value to be limited in order to protect the connected signal sink.

Parameters:

Index (hex)	Name
80nD:1C	Limiter Low Value
80nD:1D	Limiter High Value

Result:

A setpoint higher/lower than the limit values leads

to an increase of +1 in the corresponding counter index 0x90n0:06 “Limiter Low Counter” or index 0x90n0:07 “Limiter High Counter” (stored secured against power failure)
to the display Error + Overrange/Underrange in the PDO “AO Status and Error LED”
to a limitation of the electrical output in the amount of the set amplitude

By default, the limiter is set to the maximum limits of the technical OFSV and therefore has no effect.

The counter is reset

by the command x402n to index 0xFB00:01 (channel 1: n = 0, channel 2: n = 1, ...), a successful reset is shown by “255” in index 0xFB00:03 “Response”.
or by the command x4001 “Reset all AO counters”
or by changing the interface

Limiter 1: — Fig.188: CoE Index 0xFB00, “DEV Command”

During command execution, “Status” 255 “busy” is displayed in index 0xFB00:02, “0” means “successfully completed”.

The firmware responds to an unknown command with

Limiter 2: — Fig.189: General parameter incompatibility reason, 0x06040043

The limiter limits can be password protected, see section “Password protection for user data”.

Example: Sawtooth 1…7 V is output and then a “Limiter High Value” of 5 V is set:

Limiter 3: — Fig.238: Index 0x80nD set to 5 V

The overrange is counted accordingly below:

Note:

CAUTION

Consider additional protective functions!

The limiter function protects the connected load from unintentionally high or low outputs, for example due to programming errors. However, it is possible that malfunctions may occur.

Depending on the expected level of damage, additional protective functions should therefore be provided. The function may not be used for functional safety purposes!