NewTrend · dual power automatic transfer switch
Product overview
The OQ5-250A/4P is a four-pole 250 A dual-source automatic transfer switch. The original product is marked OQ5 250/4P; OQ5-250A/4P is the corresponding current-and-pole description. It has normal-source priority and transfers to the reserve source when normal power is absent and reserve power is available.
Technical selection summary
| Model labels | OQ5-250A/4P / OQ5 250/4P |
|---|---|
| Rated current | 250 A |
| Poles | 4P |
| Rated working voltage | 400 V AC |
| Frequency | 50/60 Hz |
| Motor/control marking | ~220 V on the illustrated unit |
| Insulation voltage | 800 V AC |
| Impulse withstand | 8 kV |
| Standard marking | IEC/EN60947-6-1 |
| Transfer time | Written reference: <2.5 s; parameter image: ≤2 s |
| Transfer interruption | Power is interrupted during switching |
| Source logic | Normal source first; reserve used when normal fails and reserve is present |
| Generator control | Cannot turn the generator ON or OFF |
| Modes | Manual / automatic |
| Connections | Two inputs, one load output |
| Outline reference | 370 × 172 mm face reference; further dimensions in original drawing |
Normal-source priority
When normal power is available the switch selects normal power. If normal power is unavailable and reserve power is present, it selects reserve. A separate controller is required for generator starting/stopping; the source explicitly says this switch does not perform that function.
Manual and automatic control
Set the selector to automatic for automatic source selection. Select manual mode before using the manual operating handle. The original front panel identifies both modes.
Two inputs and one output
The original rear and connection reference shows the common load output arrangement. The terminal paths must follow the original wiring diagram.
Original parameter reference
The original table below states 250 A, 400 V AC working voltage, 800 V AC insulation and a ≤2 s conversion reference. The written product description gives <2.5 s, so the version difference is retained.
Dimensions
The original drawing includes the overall face and side dimensions. Allow access to the removable terminal cover, controls and operating handle.
Wiring
The diagram identifies source I, source II, A/B/C/N conductors, control connections and load-side terminals. Wire only in accordance with the supplied unit diagram.
Typical applications
Dual-source three-phase four-wire distribution requiring manual or automatic changeover. This switch has a deliberate transfer interruption and is not a UPS.
