The NOV 10509209-001 dynamic brake resistor bank — where braking energy from a drilling drive is dissipated as heat.
Independent sourcing, not an authorized distributor. Ross Hill, NOV, and other manufacturer names and part numbers are used for reference only. Supplied as new-surplus, used-tested, or reconditioned, with condition disclosed before sale.
| Part number | 10509209-001 |
|---|---|
| Manufacturer | NOV |
| EI reference | EI-10509209-001 |
| Stock code | CA40-0800-60 |
| System | Ross Hill / Hill Hayes / NOV SCR drilling |
| Function | Dynamic braking |
| Condition | New-surplus, used-tested, reconditioned |
10509209-001 · 10509209001 · 10509209 · NOV 10509209-001 · EI-10509209-001 · CA40-0800-60 · dynamic brake resistor · dynamic braking resistor bank · DB resistor · brake resistor bank · drilling rig brake resistor
When a drilling drive brakes dynamically, the motor is driven by the load and acts as a generator. That energy has to be dissipated somewhere, and the resistor bank is where it goes — converted to heat and carried away by airflow.
These assemblies live harder than almost anything else on a rig: repeated thermal cycling, vibration, and in many installations direct weather exposure. Failures are usually blunt rather than subtle — open elements, cracked or distorted grids, and degraded terminations.
Most people reach this page from a symptom rather than a part number. These are starting points for diagnosis, not a substitute for it.
| What you are seeing | What it usually indicates |
|---|---|
| Reduced braking capability | Open element in the bank |
| Braking falls off as the assembly heats | Partially degraded elements |
| Visible cracked, burned, or distorted grids | Inspect the whole bank, not just the visible face |
| Discoloured or loose terminations | Connection resistance — common and often repairable |
| Overtemperature or airflow alarms at the bank | Cooling path obstruction before assuming element failure |
| Number | What it is | Substitute? |
|---|---|---|
| 10509209-001 | NOV dynamic brake resistor bank — the number carried on our records for this assembly. | This item |
| 0100-1000-04 | Ross Hill DWDB grid resistor assembly — drawworks dynamic braking. Related function, different assembly and numbering. | Different item |
Do not confuse this with the Ross Hill 0100-1000-04 DWDB grid resistor assembly. Both dissipate braking energy, but they are different assemblies carried under different numbering. If you are unsure which one is on your rig, send a photo of the bank and its plate. See the DWDB grid resistor page for the Ross Hill assembly.
We verify the exact dash number and revision against the physical unit before quoting, and we send photos of the plate on the unit being offered. Send a photo of your nameplate, or type out what it reads, and we will match the revision rather than guess at it.
Supplied as new-surplus (unused, from the secondary market), used-tested, or reconditioned, with condition disclosed before sale and photos on request. Availability on legacy Ross Hill and NOV equipment changes constantly — send the number and we will tell you what we can actually find.
Condition always disclosed before sale. Photos on request. Same-day response on most requests.
Condition disclosed before sale. Same-day response on most requests.