TE Connectivity 1SNA166550R0100 FIT-2/4-1 is a grey 2 x 4-pole ESSAILEC voltage test plug with a short cover, two COP-FI-1 coding pins and eight locking pins for compatible electrical test systems.
£53.68
The TE Connectivity 1SNA166550R0100, manufacturer designation FIT-2/4-1, is a grey 2 × 4-pole voltage test plug from the ENTRELEC ESSAILEC test block range. Designed for voltage transformer secondary circuits and electrical measurement systems, it provides a removable test interface for compatible ESSAILEC sockets.
The FIT-2/4-1 incorporates a short cover, 2 COP-FI-1 coding pins and 8 locking pins. Its 2 × 4-pole configuration allows testing across multiple voltage circuits while the coding arrangement helps prevent incorrect connection to incompatible ESSAILEC socket configurations.
The plug measures approximately 44 × 63 × 115 mm and weighs 91 g. Contact pins from the BRE-T series are ordered separately, allowing the appropriate contact pin to be selected for the conductor requirements of the application.
The ESSAILEC system provides a coordinated method for testing secondary electrical circuits without repeatedly disturbing permanent field wiring. The FIT-2/4-1 is specifically configured as a 2 × 4-pole plug for voltage applications, making it suitable for measurement, calibration, monitoring and protection-system maintenance.
Its 2 coding pins and 8 locking pins form part of the ESSAILEC connection concept, helping establish the intended plug/socket configuration. The separately ordered BRE-T contacts also allow the plug to be equipped with contact pins selected for the required conductor cross-section.
| Manufacturer | TE Connectivity |
|---|---|
| Brand / product family | ENTRELEC |
| Series | ESSAILEC |
| Part number | 1SNA166550R0100 |
| Manufacturer designation | FIT-2/4-1 |
| Product type | Voltage test plug |
| Configuration | 2 × 4 poles |
| Application | Voltage transformer and measurement circuits |
| Colour | Grey |
| Cover | Short cover |
| Coding | 2 × COP-FI-1 coding pins |
| Locking | 8 locking pins |
| Contact pins | BRE-T series, ordered separately |
| Rated voltage | 400 V |
| Product width | 44 mm |
| Product height | 63 mm |
| Product depth | 115 mm |
| Product net weight | 91 g |
| System rail compatibility | G32 (32 × 15 mm), TH35-7.5 (35 × 7.5 mm), TH35-15 (35 × 15 mm) |
| DIN rail standard | IEC 60715 |
| ETIM classification | EC000902 |
| Customs tariff number | 85369010 |
| EAN | 3472591665505 |
| Pack quantity | 1 piece |
The 1SNA166550R0100, designated FIT-2/4-1, is a grey 2 × 4-pole voltage test plug from the TE Connectivity ENTRELEC ESSAILEC range.
The plug has a short cover and is supplied with 2 COP-FI-1 coding pins and 8 locking pins.
No. Compatible BRE-T contact pins must be ordered separately, allowing the appropriate contact size to be selected for the application.
The voltage test plug measures approximately 44 mm wide, 63 mm high and 115 mm deep, with a net weight of 91 g.
The FIT-2/4-1 is designed for compatible ESSAILEC voltage test systems used for applications such as voltage measurement, calibration, monitoring, meter servicing and protection relay testing.
TE Connectivity ENTRELEC ESSAILEC test plugs provide purpose-designed interfaces for electrical measurement and protection circuits, helping engineers perform testing, calibration and maintenance while minimising disturbance to permanent field wiring.
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2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...