Overview
An open phase can cause negative and zero sequence currents which cause thermal stress on rotating machines and can cause unwanted operation of zero sequence or negative sequence current functions. The “Pole discordance protection (CCPDSC)” function operates based on information from auxiliary contacts of the circuit breaker for the three phases with additional criteria from unsymmetrical phase currents when required.
For more detailed information on “Pole discordance protection (CCPDSC)” function, refer to ABB, Relion 670 Series manuals.
To see other supported functions, click here.
Function Identification
| Function description | IEC 61850 identification |
IEC 60617 identification |
ANSI/IEEE C37.2 device number |
| Pole discordance protection | CCPDSC | PD | 52PD |
Signals & Setting Parameters
CCPDSC function block
CCPDSC Input signals
| CCPDSC Input signals | |||
| Name | Type | Default | Description |
| I3P | GROUP SIGNAL | – | Three phase currents |
| BLOCK | BOOLEAN | 0 | Block of function |
| BLKDBYAR | BOOLEAN | 0 | Block of function at CB single phase auto re-closing cycle |
| CLOSECMD | BOOLEAN | 0 | Close order to CB |
| OPENCMD | BOOLEAN | 0 | Open order to CB |
| EXTPDIND | BOOLEAN | 0 | Pole discordance signal from CB logic |
| POLE1OPN | BOOLEAN | 1 | Pole one opened indication from CB |
| POLE1CL | BOOLEAN | 0 | Pole one closed indication from CB |
| POLE2OPN | BOOLEAN | 1 | Pole two opened indication from CB |
| POLE2CL | BOOLEAN | 0 | Pole two closed indication from CB |
| POLE3OPN | BOOLEAN | 1 | Pole three opened indication from CB |
| POLE3CL | BOOLEAN | 0 | Pole three closed indication from CB |
CCPDSC Output signals
| CCPDSC Output signals | |||
| Name | Type | Description | |
| TRIP | BOOLEAN | Trip signal to CB | |
| START | BOOLEAN | Trip condition TRUE, waiting for time delay | |
CCPDSC Group settings (basic)
| CCPDSC Group settings (basic) | |||||
| Name | Values (Range) | Unit | Step | Default | Description |
| Operation | Off On |
– | – | Off | Operation Off / On |
| tTrip | 0.000 – 60.000 | s | 0.001 | 0.300 | Time delay between trip condition and trip signal |
| ContSel | Off PD signal from CB Pole pos aux cont. |
– | – | Off | Contact function selection |
| CurrSel | Off CB oper monitor Continuous monitor |
– | – | Off | Current function selection |
| CurrUnsymLevel | 0 – 100 | % | 1 | 80 | Unsym magn of lowest phase current compared to the highest. |
| CurrRelLevel | 0 – 100 | %IB | 1 | 10 | Current magnitude for release of the function in % of IBase |
CCPDSC Non group settings (basic)
| CCPDSC Non group settings (basic) | |||||
| Name | Values (Range) | Unit | Step | Default | Description |
| GlobalBaseSel | 1 – 12 | – | 1 | 1 | Selection of one of the Global Base Value groups |
CCPDSC Monitored data
| CCPDSC Monitored data | ||||
| Name | Type | Values (Range) | Unit | Description |
| IMin | REAL | – | A | Lowest phase current |
| IMax | REAL | – | A | Highest phase current |
Logics & highlights
Pole discordance external detection logic
Pole discordance signals for internal logic
Simplified block diagram of pole discordance function CCPDSC – contact and current based
