There are two main operational modes:
- Beam measurement mode, in which EGP is inactive and the extraction field on the HV cage is 4 kV.
- MCP calibration mode, in which EGP is active and the extraction field on the HV cage is 2 kV.
Typical settings for both modes are:
| beam measurement | MCP calibration | |
| EGPin | -1800 V | -1500 V |
| EGPout | -1900 V | -1100 V |
| Cgrid | -2000 V | -1000 V |
| MCPin | 2000 V | 1000 V |
| MCPout | 2600 V | 1600 V |
| Phosphor | 5000 V | 4000 V |
The HV settings is done through FESA navigator or BGI expert application (Ana). No HV control is given to machine operators.
In the past the sudden change of HV gave issues with pressure in IR4 leading to beam dumps, therefore HV settings must be operated very carefully.