Four decisions to make before quoting an ATS
Confirm these four items before requesting pricing so each supplier quotes the same basic ATS configuration.
Transition, poles, service rating, and fault-current capability are design decisions. Ampacity alone is not enough to quote an ATS responsibly.
1. Transition type
Choose open, delayed, closed, or bypass isolation based on load interruption tolerance, motor residual voltage, maintenance needs, and utility requirements. Do not use closed transition as a generic premium upgrade; momentary source paralleling brings additional coordination.
2. Number of switched poles
The grounding design determines whether the neutral is solid or switched. Confirm three pole versus four pole with the engineer and one line.
3. Service entrance rating
When the ATS is service equipment, it needs the required disconnecting, protection, grounding, and markings. Identify utility metering and local service rules at the same time.
4. Withstand and closing rating
Provide available fault current and upstream protective-device details. The applicable rating can depend on a specific breaker or fuse combination and clearing time.
QUOTE CHECKLIST
Information to send with the RFQ
- 01Amps and voltage
- 02Poles
- 03Transition type
- 04Service entrance
- 05Available fault current
- 06Upstream device
- 07NEMA enclosure
- 08Controller accessories
Sources and further reading
Project requirements and adopted codes control. Use these manufacturer and standards-organization resources as technical starting points.
READY TO QUOTE?