BECKHOFF EL9xxx System Terminal Guide

10.4 Potential group and insulation testing

When mixing 24V and 230V power contacts at the same terminal station, EL9080 must be inserted between different voltage groups. Before conducting insulation tests (such as voltage withstand tests on 230V circuits), all PE feeders should be disconnected, as coupling between PE contacts and rail capacitors may cause the tester to misjudge.

Explosion proof special conditions (ATEX/IECEx/cFMus)

Many EL9xxx terminals (EL9011, EL9100, EL9180, EL9195, EL9400, EL9540, etc.) have obtained explosion-proof certification. When using in Zone 2 or Class I Division 2 areas, the following must be followed:

Installed in an enclosure with at least IP54 rating.

Pollution level ≤ 2, transient overvoltage ≤ 119   V (for 24   V systems) or 140% of rated voltage.

Temperature range: Standard terminal 0... 55   ℃; Extended temperature (ET) terminal -25...+60 ℃.

Do not plug or unplug while live, and do not adjust fuses or wiring in explosive environments.

For feed terminals with fuses (such as EL9200), power must be disconnected before replacing the fuse.

Please refer to the nameplate on the side of the terminal for specific explosion-proof markings (such as II 3 G Ex nA IIC T4 Gc).

Diagnosis and troubleshooting checklist

Possible causes and solutions for the phenomenon

E-bus communication interruption, RUN LED off, end not installed with EL9011/EL9012, end cover installed

The power contact voltage is normal, but there is no power supply potential group at the downstream terminal. The EL9080 is interrupted or not fed. Check if EL9080 is inserted; If necessary, install a feeding terminal on the right side

The FuseError of EL9210 in TwinCAT is TRUE. After the internal fuse is blown and the power is cut off, replace the 6.3-A slow melting fuse (only applicable to EL9200/9210/9250/9260)

The Diagnosis LED (Us) of EL9410 has a red E-bus power supply voltage below 17V. Check the 24V input of EL9410; Measure the voltage at 1/5 of the terminal

The analog signal fluctuates greatly, and EL9540-0010 reports overvoltage power supply line surge or poor voltage regulation. Add EL9550 or external surge protector at the front end

Motor regeneration energy causes overvoltage alarm (EL9570 overload LED is always on). The regenerated energy exceeds the capacitor capacity, and the braking resistor is not connected to the 10 Ω/10 W braking resistor

Standard terminals in security applications affect PL level. Non interfering terminals are not used or hardware versions are too low. Check the hardware version number; Adopting grounding feedback and full pole cut-off wiring