6- Reverse Power Protection (32) | Generator Motoring & Testing Explained

In this video, we dive into Reverse Power Protection – ANSI 32, with a focus on motoring protection for turbine-driven generators, especially steam units.
You’ll learn how the reverse power relay detects power flowing into the generator, why motoring is dangerous for different prime movers, and how sequential trip logic protects the turbine during shutdown. We’ll also walk through step-by-step test procedures using OMICRON Test Universe.

🔍 What you’ll learn:
• Concept and purpose of reverse power (32) protection
• How a generator becomes a motor when mechanical input is lost
• Typical reverse power settings (%Pn, time delays) for steam, diesel and hydro units
• Electrical motoring protection using reverse power relays (P = V · I · cosφ)
• Mechanical motoring protection methods (oil pressure, exhaust hood temperature, ΔP, etc.)
• Consequences of motoring on steam, hydro, gas turbines and engines
• Sequential trip logic – safely closing valves and tripping the breaker/field
• Test formulas for per-unit reverse power and low power factor conditions
• How to test pick-up, trip time, and seal-in time for function 32
• How to perform reverse power tests with and without emergency tripping in Test Universe

0:00 – Introduction to Reverse Power (32) Protection
01:45 – Motoring behaviour of generators
04:11 – Consequences of motoring on different prime movers
05:10 – Mechanical motoring protection methods
6:16 – Electrical motoring protection methods
07:34 – Sequential trip logic (prime mover → breaker → field)
08:30 – Test formulas & per-unit power calculations
09:28 – Testing the reverse power pick-up test (ramping concept)
13:46 – Trip time test without emergency tripping
15:09 – Seal-in time test
16:45 – Trip time test with emergency tripping (stop valve signal)