QF-48 Field-Mounted Surge Protector (Parallel, N/I Thread Optional)
2-wire, 3-wire, 4-wire, etc. Function: line-to-line low residual voltage protection, for protection of LPZ0B to LPZ2 zones and subsequent zone boundaries.
- Original Factory Genuine, Tenfold Compensation for Counterfeits
- Full Machine Warranty, Lifetime Maintenance
- In Stock, Shipped on the Same Day
The surge protective device provides line-to-line low residual voltage protection, for protection of LPZ0B to LPZ2 zones and subsequent zone boundaries. It can be used for protection of 2-wire, 3-wire and 4-wire 24Vdc transmitters, flow meters, RS-485, solenoid valves and other products.
Ordering code:QF2-48-□ denotes 2-wire, QF3-48-□ denotes 3-wire, QF4-48-□ denotes 4-wire; □: N=1/2″NPT, I=M20×1.5, X/Y/Z are custom threads.
| Parameter Name | Technical Specifications |
|---|---|
| Basic Parameters | |
| Nominal voltage Un | 24V |
| Max. continuous DC operating voltage Uc | 33V |
| Max. continuous AC operating voltage Uc | 23.3V |
| wire system | 2-wire/3-wire/4-wire |
| Discharge parameters | |
| Lightning impulse current per wire Iimp (10/350μs, D1) | 2.5kA |
| Maximum discharge current Imax (8/20μs, C2) | 10kA |
| Nominal discharge current per wire In (8/20μs, C2) | 5kA |
| Protection level and response | |
| Protection voltage Up (8/20μs, C2) | L-L≤60V / L-PE≤600V |
| Frequency range fG (100Ω characteristic impedance) | 1.0MHz |
| Response time Ta | <1 ns |
| Mechanical & Environmental | |
| Thread specification (optional) | M20×1.5, 1/2" 14NPT, G 1/2" etc. (male thread) |
| Earthing method | Wire grounding |
| Installation Method | Parallel |
| Output conductor specification | 1.5mm², length 250mm, flexible multi-strand, abrasion-resistant |
| Housing material | 304/316 stainless steel etc. |
| Degree of protection | IP67 |
| Flammability rating (UL94) | V0 |
| Operating temperature range | -40℃~+80℃ |
| Test standard | IEC 61643-21 / GB/T 18802.21 |
- 2-wire, 3-wire, 4-wire
- M20×1.5 and other thread options
- Low voltage protection level, direct protection of terminal equipment
- Parallel-type field-mounted module
- 304/316 stainless steel housing
- Suitable for 24V signal circuits in hazardous areas.
Field instrument surge protection
Suitable for surge protection of 24Vdc transmitters, flow meters, RS-485, solenoid valves and other field instruments in hazardous areas; installed in parallel at the field instrument junction box.
Need selection advice or bulk quotation?
Send us the working condition parameters (signal type, medium, range, pressure, temperature, connection method), and our engineers will provide a selection scheme and quotation within 1 working day.
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