Eaton ATC-300+/800/900: switchgear-integrated ATS controllers
The ATC-3xx/8xx/9xx family is not a standalone switch: these are microprocessor controllers that pair with a contactor, MCCB or Magnum breaker already specified into a customer’s switchgear, typically covering the 100 to 4000 A range that Eaton publishes for automatic transfer switch controllers generally. ATC-900 adds waveform recording and power-quality metering on top of ATC-300+’s core automatic transfer logic.
Technical specification
| Model | Current | Poles | Voltage | Transfer time | Type | Mounting | Control / comms |
|---|---|---|---|---|---|---|---|
| ATC-300+ | 100–4000 A (typical) | – | – | – | Panel | Switchgear-integrated | Microprocessor controller |
| ATC-800 | 100–4000 A (typical) | – | – | – | Panel | Switchgear-integrated | Microprocessor controller |
| ATC-900 | 100–4000 A (typical) | – | – | – | Panel | Switchgear-integrated | Microprocessor controller, waveform capture |
Source of the values: Eaton Automatic Transfer Switch brochure (ATC-300+/600/800/900). This is not a standalone switch: the ATC-3xx/8xx/9xx controllers pair with a contactor, MCCB or Magnum breaker already built into the customer’s switchgear. Confirm the breaker type and ampere rating against the actual panel before quoting; the ampere range shown is Eaton’s general published range for this controller family, not per-code. An en dash means the manufacturer does not publish that value in the source we hold; we do not fill it in with an estimate. Confirm every figure against the current manufacturer document before it is written into a contract.
The references we quote in this family are ATC-300+, ATC-800 and ATC-900. Send us the load, the phase and the transfer requirement, and we will confirm availability and lead time.
Which one should you choose?
This is a controller quote, not a breaker quote
Because the controller pairs with switchgear the customer (or their panel builder) already specifies, our quote for this family covers the controller itself; the contactor, MCCB or Magnum breaker and its ampere rating come from the panel design, not from us. Confirm which breaker type the panel builder is using before specifying a controller.
ATC-900’s extra metering is worth it when power quality is already a concern
If the site already tracks THD, waveform events or has a history of power-quality complaints, ATC-900’s recording capability turns the transfer switch into a diagnostic tool as well as a redundancy device. For a site with clean, stable power, the simpler ATC-300+ logic is enough and costs less.
Compatibility with third-party monitoring is a real integration point
These controllers are built to be compatible with Eaton’s own DCT and broader building/power monitoring platforms, which matters when the ATS needs to report into a site-wide power monitoring system rather than standing alone. Confirm the monitoring platform in use before assuming out-of-the-box compatibility.
Lead time on this family follows the panel builder’s schedule, not ours alone
Because the controller ships to integrate into switchgear that a panel builder is assembling, the overall project timeline usually depends on the panel build schedule as much as on controller availability. Coordinate the order date with the panel builder’s own milestones rather than treating the controller as an independent line item.
Where it fits, and where it does not
Fits a project where the switchgear and breaker are already specified by a panel builder and only the automatic transfer control logic is being sourced from us. Does not fit a request for a complete standalone transfer switch; see the wall-mounted or rack ATS pages for a self-contained unit.
What we need in order to quote it
- Breaker type already specified in the panel (contactor, MCCB or Magnum)
- Ampere rating of that breaker
- Whether power-quality recording (ATC-900) is needed
- Monitoring platform the ATS needs to report into, if any
Request a Quote
Tell us the usable capacity, the protocol and the delivery country. A priced quote comes back within 48 hours, usually with a second option so the trade-off is visible.
