NewTrend · automatic phase selector switch
Product overview
NewTrend PS8-16 monitors a three-phase, four-wire supply and automatically selects a phase with normal voltage to feed a single-phase load. Inputs are L1, L2, L3 and N; the output is L and N. It provides adjustable overvoltage and undervoltage thresholds, true RMS voltage/current monitoring and adjustable overcurrent protection. Select the 63A or 80A AC-1 contact version. The 72mm-wide device mounts on a DIN rail and indicates the selected phase and fault status.
Technical selection summary
| Model | PS8-16 |
|---|---|
| Function | Automatic phase selection with overcurrent protection |
| Supply input | L1, L2, L3 and N; three-phase four-wire |
| Load output | L and N; single-phase |
| Rated supply voltage | AC 220V (each L1/L2/L3 to N) |
| Supply frequency | 45-65Hz |
| Operating voltage range | 80-400V (L1/L2/L3-N) |
| Rated operational current | 63A / 80A, AC-1 |
| Measurement | True RMS voltage and current |
| Power input | Maximum 3VA |
| Overvoltage setting | OFF or 230-300V |
| Undervoltage setting | 140-210V or OFF |
| Voltage-fault action delay | 0.1-10s |
| Overcurrent setting | 1-63A, including the 80A contact version |
| Overcurrent action delay | 2-600s |
| Power-up delay | 2-600s |
| Reset delay | 2-900s |
| Measurement error | ≤1% |
| Electrical life (AC-1) | 10,000 operations |
| Mechanical life | 1,000,000 operations |
| Operating temperature | -20 to +60°C |
| Storage temperature | -35 to +75°C |
| Mounting | DIN rail to EN/IEC 60715 |
| Protection | IP40 front panel / IP20 terminals |
| Operating position | Any |
| Overvoltage category / pollution degree | III / 2 |
| Body dimensions | 82 x 72 x 68mm |
| Weight (current catalogue) | 320g |
| Isolation function | Not provided; disconnect upstream circuit breaker before maintenance |
Operation
- Connect the three-phase four-wire supply to L1, L2, L3 and N and the single-phase load to L and N, following the exact factory diagram.
- The controller selects a phase with normal voltage. If the active phase develops a voltage fault, it transfers to a phase within the configured voltage limits. The fault indicator lights when all three phases are abnormal.
- Set overvoltage to OFF or 230-300V and undervoltage to 140-210V or OFF. Voltage-fault action delay is 0.1-10s, power-up delay 2-600s and reset delay 2-900s.
- The original diagrams show operation with automatic fault reset enabled and disabled. Observe the illustrated transfer interval and use loads compatible with an interrupted supply.
- Set overcurrent within 1-63A with a 2-600s delay. The 80A contact version does not extend the catalogue overcurrent setting beyond 63A.
Typical applications
- Single-phase loads supplied from a three-phase four-wire distribution system
- DIN-rail control panels requiring automatic selection of an available normal-voltage phase
View or download PS8-16 automatic phase selector catalogue, September 2026 (PDF)
Product reference images and drawings
Exact-model selection, technical ratings and wiring
Phase-selection timing, connection example and dimensions
This device has no isolation function. Disconnect the upstream circuit breaker before maintenance. Follow the exact L1/L2/L3/N input and L/N output wiring; provide coordinated upstream circuit and short-circuit protection. Phase transfer includes the interval shown in the factory timing diagram and is not a zero-interruption UPS function. Installation and wiring must be performed by qualified electricians.
