Drilling Rig Electrical · Generator synchronising
Ross Hill 0000-8500-18 — AutoSync AC II Module
The engine-calibrated variant of the AutoSync AC II generator-synchronising module — and why it is not a drop-in for a 0000-8500-00.
The engine-calibrated variant of the AutoSync AC II generator-synchronising module — and why it is not a drop-in for a 0000-8500-00.
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 | 0000-8500-18 |
|---|---|
| Manufacturer | Ross Hill / NOV |
| EI reference | EI-0000-8500-18 |
| System | Ross Hill / Hill Hayes / NOV SCR drilling |
| Function | Generator synchronising — engine-calibrated variant |
| Condition | New-surplus, used-tested, reconditioned |
0000-8500-18 · 0000850018 · 00008500-18 · 0000-8500 · 8500-18 · AutoSync AC II · Auto-Sync · Auto Sync · AC Module Auto Sync · EI-0000-8500-18
The AutoSync AC II is the control that brings an incoming generator into synchronism with the running bus — matching voltage, frequency, and phase angle — and issues the permissive to close. On a diesel-electric rig, sets are paralleled and dropped as load changes, so this function runs constantly.
What makes the -18 worth its own page is that the dash suffix on this family is an engine calibration, not a revision level. The module has to be matched to the engine it is watching: the flywheel tooth count and magnetic-pickup frequency the card expects are set by the calibration. Fit the wrong one and it will bolt in, power up, and still fail to sync the set properly.
These are the figures our file carries against the -18. Treat them as a starting point for identification, not as a specification for your set — confirm against the unit and the engine before ordering.
| Parameter | Recorded value |
|---|---|
| Engine | CAT 3512B |
| Rated speed | 1200 RPM |
| Generator output | 600 V 3-phase 60 Hz |
| Flywheel teeth | 183 |
| Magnetic pickup | 3660 Hz @ 1200 RPM |
| Timing constant on plate | 199.4 µsec |
| PMG | 240 VAC 120 Hz 1-phase |
One useful internal check: 183 flywheel teeth turning at 1200 RPM produce 3660 pulses per second, which is exactly the pickup frequency recorded. The two figures corroborate each other, which is a good sign that the calibration record is sound. It is still not a substitute for reading your own nameplate.
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 |
|---|---|
| A replacement module was fitted and the set still will not sync | Calibration mismatch — check the dash number against the engine |
| Set syncs on one engine but not on an otherwise identical one | Different calibration between the two modules |
| Sync is slow or hunts before closing | Matching loop degraded or drifting |
| Hard or rough closure when paralleling | Out-of-phase closure risk — stop and investigate before repeating |
| Intermittent behaviour that worsens with vibration | Check card-edge connectors before condemning the card |
| Number | What it is | Substitute? |
|---|---|---|
| 0000-8500-18 | AutoSync AC II, the calibration covered by this page. | baseline |
| 0000-8500-00 | Same module family, base number. Rev C and Rev E both confirmed in service. A different calibration from the -18. | NOT a substitute |
| 0001-2657 | AC Module Auto Sync Aux II PCB — the auxiliary card inside the assembly, and frequently the item that actually failed. | Different item |
| 0001-2656-00 | 3-phase AC control module, EMD engine applications. | Different engine family |
We do not claim that any two dash numbers in this family are interchangeable. If you need to move a module between sets, send us both dash numbers and both engine configurations and we will tell you what we can and cannot confirm.
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 calibration rather than guess at it.
These are the details that let us identify the right unit instead of guessing 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.