Downhole · ESP
ESP Power Cable
The three phase cable that carries power from surface to the motor, strapped to the outside of the tubing all the way down.
What it does
Delivers motor power and, in most systems, also carries the downhole sensor signal. Round cable is tougher and more flexible; flat cable fits tight casing clearances.
Basics
| Shapes | Round or flat |
| Conductors | Copper, solid or stranded, typically #1 to #6 AWG |
| Insulation | Polypropylene (lower temperature) or EPDM |
| Barrier | Lead sheath for gassy or sour wells |
| Armour | Galvanized steel, stainless or Monel |
| Option | Integrated capillary tube for chemical injection |
Common failures
- Insulation breakdown from heat or gas decompression
- Mechanical damage while running in hole
- Corrosion of the armour in sour wells
Troubleshooting
- Symptom
- Low insulation reading to ground
- Likely cause
- Damaged insulation along the cable or at a splice
- What to check
- Test sections from the junction box to locate the fault
- Symptom
- Ground fault right after installation
- Likely cause
- Cable pinched or cut while running
- What to check
- Review running speed, protectors and tight spots