Resistor bridge

The EP3356 enables the connection of a resistor bridge or load cell in a 4-wire connection technology.

Resistor bridge 1:
Resistor bridge

The cable shield must be connected to pin 5 of the M12 connector.

The four M12 sockets of the EP3356 are internally connected to one another. Therefore, you can connect a resistor bridge to any M12 socket.

You can also connect several resistor bridges in parallel: Example.

The voltage Uref is 10 V and is generated in the EP3356 from UP.

Do not earth the sensor cable shield at the sensor end

If a shielded sensor cable is used, it should not be earthed at the sensor end. Otherwise measurement deviations may occur in certain system configurations.

Meanings of the LEDs

Resistor bridge 2:
LEDs EP3356-0022

LED

Color

Meaning

RUN

green

This LED indicates the boxes operating state:

off

State of the EtherCAT State Machine: INIT = Initialization of the box

blinking

State of the EtherCAT State Machine: PREOP = Setting for mailbox communication and variant standard settings

single flash

State of the EtherCAT State Machine: SAFEOP = Channel checking of the Sync Manager and the Distributed Clocks: Outputs stay in safe operation mode

on

State of the EtherCAT State Machine: OP = Normal operation mode, mailbox- and process data communication possible

flickering

State of the EtherCAT State Machine: BOOTSTRAP = mode for firmware updates of the box

Stdy

green

on

The measuring value is steady

off

The measuring value is not steady

Msr

grün

on

Measuring active (valid process data)

off

  • Self-calibration active (if LED self calibration is lit) or
  • Self-test active (if LED self test is lit)
  • filters are initialized

S-Cal

green

on

Self-calibration active

  • Process data are not valid

S-Test

green

on

Self-test active

  • Process data are not valid

ErrD

red

on

Channel 1 (strain gauge differential signal) is out of valid value range.

ErrR

red

on

Channel 2 (reference voltage) is out of valid value range. Possible reasons:

  • The reference voltage Uref is not present. Check if the supply voltage UP is present: Uref is internally generated from UP.
  • The reference voltage Uref has dropped due to overload.