Overcurrent protection
Both output voltages (US and UP) on each EtherCAT P port are protected against overcurrent.
The overcurrent protection can be divided into several operating ranges:
(1) Nominal operation
The overcurrent protection is inactive in nominal operation.
(2) Overcurrent
If the nominal current In is exceeded, this is detected as overcurrent. A warning message is output.
If the overcurrent persists, the respective output voltage is switched off in accordance with the tripping characteristic and an error message is output.
The nominal current and the tripping characteristic can be parameterized individually for each output current:
- Nominal current In:
CoE Index 80x0:12 "Nominal Current Us"
CoE Index 80x0:13 "Nominal Current Up"
Value range: see chapter Technical data. - Tripping characteristic:
CoE Index 80x0:11 "Characteristic"
The tripping characteristic is comparable with that of fuses. The fuse blows with a delay, depending on the magnitude of the overcurrent:
Current | Very fast acting | Fast acting | Slow acting | Time delay |
|---|---|---|---|---|
100 % In | 1 h | - | - | - |
110 % In | 1 h | 4 h | - | - |
120 % In | 7 min | 4 h | - | - |
150 % In | 30 s | 30 min | 1 h | 4 h |
210 % In | 500 ms | 20 s | 20 s | 100 s |
275 % In | 500 ms | 1 s | 20 s | 10 s |
300 % In | 20 ms | 100 ms | 1 s | 3 s |
(3) Current limitation
The current limitation limits each output current to ILim. ILim is higher than the nominal current In.
The current limitation switches the supply voltage of the respective output off if it has to limit the current for longer than tLim. An error message is output.
ILim and tLim cannot be parameterized. See chapter Technical data.
The delay of the switch-off procedure by tLim allows short-term overcurrents in order among other things to switch capacitive loads.
Current limitation and overcurrent protection are active at the same time. Depending on the parameterization it may be the case that the overcurrent protection switches an output off before tLim has expired.
(4) Malfunction
In case of a malfunction of overcurrent protection and current limitation, each output voltage is protected by a short-circuit protection. The short-circuit protection is dimensioned such that it only becomes active if the overcurrent protection and current limitation fail.
As a last resort, each output voltage is protected by a fuse. If the fuse has blown the box is defective. The fuse specifications can be found in the chapter Technical data.
Resetting an error state
If an output voltage has been switched off by the overcurrent protection, it can be activated again through one of the following actions:
- a positive edge on the output variables
"DPO Inputs Channel n" > "Reset Ux" of the respective EtherCAT P port
(n = 0 for X52, n = 1 for X53, n = 2 for X54, n = 3 for X55) - a positive edge on the output variables
„DPO Outputs Device“ > „Global Reset“
The error message is also reset as a result.