Cummins 400 Amp Automatic Transfer Switch
Cummins 400 Amp Automatic Transfer Switch
Cummins 400 Amp Automatic Transfer Switch — OTEC400 (NSE)
Lead time = 13 to 16 weeks
Keep critical loads online with the Cummins 400 Amp Automatic Transfer Switch (OTEC400, NSE). Built for dependable, seamless transfer between utility and generator power, this 400A ATS comes in your choice of NEMA 1 (indoor) or NEMA 3R (outdoor) enclosures, multiple voltages, and both 3-phase and 1-phase configurations. As an Authorized Cummins Dealer, AllProGenerators.com provides expert guidance and phone support to help you choose the right option for your installation.
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Available Models (8 Options)
| MPN | Model | Phase | Amps | Voltage | Enclosure |
|---|---|---|---|---|---|
| A075F127 | OTEC400 (NSE) | 3-Phase | 400A | 208V | NEMA 1 (Indoor) |
| A075F128 | OTEC400 (NSE) | 3-Phase | 400A | 240V | NEMA 1 (Indoor) |
| A075F129 | OTEC400 (NSE) | 3-Phase | 400A | 480V | NEMA 1 (Indoor) |
| A075F130 | OTEC400 (NSE) | 3-Phase | 400A | 208V | NEMA 3R (Outdoor) |
| A075F131 | OTEC400 (NSE) | 3-Phase | 400A | 240V | NEMA 3R (Outdoor) |
| A075F132 | OTEC400 (NSE) | 3-Phase | 400A | 480V | NEMA 3R (Outdoor) |
| A075F133 | OTEC400 (NSE) | 1-Phase | 400A | 240V | NEMA 1 (Indoor) |
| A075F134 | OTEC400 (NSE) | 1-Phase | 400A | 240V | NEMA 3R (Outdoor) |
NSE = Non-Service Entrance. Always verify local code requirements and compatibility with your generator and load center.
Key Highlights
- 400 Amp capacity for robust residential and light commercial standby systems
- Automatic transfer from utility to generator power with minimal interruption
- Multiple configurations: 1-phase or 3-phase, 208/240/480V
- NEMA 1 (indoor) or NEMA 3R (outdoor) weather-resistant enclosure
- Engineered by Cummins — a global leader in power generation
- Clean wiring layout for installers and straightforward serviceability
- Authorized dealer support from AllProGenerators.com
Specifications
| Manufacturer | Cummins Power Generation |
| Series | OTEC (Automatic Transfer Switch) |
| Model | OTEC400 (NSE) |
| Amperage | 400A |
| Voltage Options | 208V, 240V, 480V (see variant table) |
| Phase Options | 1-Phase (240V) and 3-Phase (208V/240V/480V) |
| Enclosure | NEMA 1 (Indoor) or NEMA 3R (Outdoor) |
| Operation | Automatic transfer between utility and generator |
| Application | Residential / Light Commercial standby power |
| Compliance | Refer to local code & inspector requirements |
Need help choosing? Call our U.S. team for personalized guidance. We’ve supported Cummins customers since 2018 with real phone support and fast fulfillment.
Frequently Asked Questions
Q: What’s the difference between NEMA 1 and NEMA 3R?
A: NEMA 1 is for indoor installs. NEMA 3R is outdoor-rated and protects against rain and ice.
Q: Should I choose 1-phase or 3-phase?
A: Most homes are 1-phase (240V). Many commercial sites require 3-phase (208/240/480V). Your electrician can confirm.
Q: What does “NSE” mean?
A: Non-Service Entrance (no integral main disconnect). If a service-entrance rated switch is required by code, consult your AHJ/electrician.
Q: Is this compatible with all Cummins generators?
A: It’s designed for Cummins standby systems. Confirm the generator voltage/phase and control wiring with your installer.
Q: Lead times and shipping?
A: Lead times vary by configuration. Contact us for current availability and freight options.