ABB OTM_C + ATS021/022: switch-disconnector with separate ATS control
This is ABB’s classic split ATS architecture: an OTM_C switch-disconnector, sized separately per project, paired with a dedicated ATS021 or ATS022 automatic transfer controller. Where TruONE ships as one factory-integrated unit, this pairing is assembled from two components chosen to match the specific installation.
Technical specification
| Model | Current | Poles | Voltage | Transfer time | Type | Mounting | Control / comms |
|---|---|---|---|---|---|---|---|
| OTM_C + ATS021/022 | (depends on OTM_C size chosen) | – | – | – | Panel | Switchgear-integrated | ATS021/022 controller |
Source of the values: ABB OTM_C switch-disconnector with ATS021/022 controller (new.abb.com). This is a classic split architecture: an OTM_C switch-disconnector (sized separately per project) paired with a dedicated ATS021 or ATS022 automatic controller, rather than a single all-in-one unit like TruONE. Current rating depends entirely on which OTM_C body is selected; confirm the load before specifying. 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 OTM_C + ATS021/022. Send us the load, the phase and the transfer requirement, and we will confirm availability and lead time.
Which one should you choose?
Sizing starts with the OTM_C body, not the controller
Because current rating depends entirely on which OTM_C switch-disconnector is selected, the first question in any quote for this architecture is the load, not which ATS controller to use. Confirm the amperage before discussing ATS021 versus ATS022.
This architecture suits a retrofit onto existing switchgear better than a factory-integrated unit does
Because the switch and controller are separate components, this pairing can be specified around switchgear dimensions and bus configurations that already exist on site, which is harder to do with an all-in-one unit like TruONE that ships as a fixed physical package.
Choosing between ATS021 and ATS022 needs a direct answer from ABB
We have not confirmed the functional difference between the two controllers in the sources checked for this page; ask us to get the comparison directly from ABB before recommending one over the other for a specific project.
Keep the switch and controller documentation together in the proposal
Because this architecture is genuinely two separate components, a proposal should reference the OTM_C datasheet for the switch body and the ATS021/022 documentation for the controller separately rather than treating it as one combined datasheet, which does not exist for this pairing the way it does for TruONE.
A split architecture also means two separate spare-parts conversations
If the OTM_C body or the ATS021/022 controller ever needs replacement, they are ordered and stocked separately rather than as one spare-parts number, which is worth explaining to a customer used to an all-in-one product’s simpler spares model.
Where it fits, and where it does not
Fits a retrofit or a project where the switchgear dimensions and OTM_C sizing are already being worked out with a panel builder. Does not fit a project wanting a single pre-integrated unit ordered by one code; see the TruONE page for that.
What we need in order to quote it
- Load current, to size the OTM_C body first
- Whether ATS021 or ATS022 is required (ask us to confirm the difference with ABB)
- Existing switchgear dimensions and bus configuration
- Whether this is a retrofit onto existing equipment
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.
