SP21 Series Waterproof Connectors
IP68 Threaded Connections for Power & Signal
Reliable and cost-effective connections for industrial, outdoor, and electrical equipment.
High-Current IP68 Threaded Connectors for Power & Signal Connections
INTE-AUTO SP21 Series connectors are IP68 waterproof threaded connectors designed for reliable power and signal connections in industrial, outdoor, and demanding equipment environments. As the largest series among SP13, SP17, and SP21, SP21 supports larger cables, more contact configurations, and higher-current connection requirements.
The series is available with 2, 3, 4, 5, 6, 7, 9, and 12 contacts, with rated current up to 30 A and rated voltage up to 500 V AC depending on the selected configuration. Selected 5- and 6-contact versions combine different contact sizes within the same connector, providing additional flexibility for circuits with different current requirements.
With cable OD options of 4.5–7.0 mm and 7.0–12.0 mm, SP21 Series connectors accommodate a broad range of cable constructions. IP68 protection, secure threaded coupling, gold-plated brass contacts, and multiple contact arrangements make the series a cost-effective solution for equipment requiring reliable waterproof power and signal connections.
SP21 Series Waterproof Connectors
SP21 Connector Series Types
INTE-AUTO SP21 Series connectors are available in multiple cable-mounted and panel-mounted configurations for different cable-to-cable and cable-to-equipment connection requirements.
SP21 Plug
Cable-mounted plug with threaded coupling for secure and reliable mating. Available in multiple contact configurations for power, signal, and mixed-current connection requirements.
SP21 Cable Receptacle
Cable-mounted receptacle for cable-to-cable connections, extension cables, and customized waterproof cable assemblies.
SP21 Fixed Receptacle
Equipment-mounted receptacle for integrating the SP21 Series connection interface into control units, power equipment, instruments, and other electronic systems.
SP21 Flange Receptacle
Panel-mount receptacle with a flange structure for secure installation on equipment enclosures and control panels. Suitable for applications requiring a stable equipment-side connection and defined panel mounting interface.
Technical Specifications
| Specification | SP21 Series |
|---|---|
| Number of Contacts | 2 / 3 / 4 / 5 / 6 / 7 / 9 / 12 |
| Mating | Threaded coupling |
| IP Rating | IP68 |
| Cable Outer Diameter | A: 4.5–7.0 mm / B: 7.0–12.0 mm |
| Outshell Material | Nylon 66, V-0 flame-retardant grade |
| Insert Material | PPS |
| Contact Material | Gold-plated brass |
| Wiring Method | Soldering |
| Mating Cycles | ≥500 |
| Operating Temperature | -25°C to +85°C |
| Insulation Resistance | 2000 MΩ |
Electrical Specifications
| Contacts | Contact Configuration | Rated Current | Rated Voltage (AC V) | Test Voltage (AC V), 1 min | Contact Resistance | Wire Size (mm² / AWG) |
| 2 | 2.8 × 2 | 30A | 500 | 1500 | 1 mΩ | <4.17 / 11 |
| 3 | 2.8 × 3 | 30A | 500 | 1500 | 1 mΩ | <4.17 / 11 |
| 4 | 2.8 × 4 | 30A | 500 | 1500 | 1 mΩ | <4.17 / 11 |
| 5 | 2.8 × 5 | 30A | 500 | 1500 | 1 mΩ | <4.17 / 11 |
| 5 | 2.8 × 2 + 1.0 × 3 | 5A / 30A | 500 | 1500 | 5 / 1 mΩ | <0.785 / 18 + <4.17 / 11 |
| 5 | 1.8 × 5 | 15A | 500 | 1500 | 2.5 mΩ | <2 / 14 |
| 6 | 1.8 × 6 | 15A | 500 | 1500 | 2.5 mΩ | <2 / 14 |
| 6 | 2.8 × 4 + 1.0 × 2 | 30A / 5A | 500 / 400 | 1500 | 1 / 5 mΩ | <0.785 / 18 + <4.17 / 11 |
| 6 | 2.8 × 2 + 1.0 × 4 | 30A / 5A | 500 / 400 | 1500 | 0.5 / 5 mΩ | <10 / 7 + <0.785 / 18 |
| 7 | 1.8 × 7 | 15A | 500 | 1500 | 2.5 mΩ | <2 / 14 |
| 9 | 1.0 × 9 | 5A | 400 | 1500 | 5 mΩ | <0.785 / 18 |
| 12 | 1.0 × 12 | 5A | 400 | 1500 | 5 mΩ | <0.785 / 18 |
Connector Cross-Section Diagram
Find the Right SP21 Series Connector for Your Outdoor Application
Share your contact configuration, current, voltage, wire size, cable OD, installation method, and operating environment. INTE-AUTO will help you select the appropriate SP21 Series connector or develop a complete custom cable assembly for your equipment.
SP21 Series Connectors Applications
SP21 Series connectors provide secure IP68 power connections for submersible pumps and feed pumps operating in wet environments. Their threaded locking and high-current capability help maintain reliable power transmission under continuous outdoor use.
SP21 Series connectors are suitable for UV-C sterilizer ballast wiring where stable power transmission and moisture resistance are required. The IP68 design helps protect electrical connections in water-treatment equipment.
SP21 Series connectors can support power and control connections for automated chemical dosing systems. Multiple contact configurations make them suitable for combining power, control, and sensor circuits in one waterproof interface.
SP21 Series connectors provide reliable signal and power connections for digital flow meters and pressure sensors installed in wet or industrial environments. The threaded coupling helps prevent accidental disconnection during equipment operation.
SP21 Series connectors are suitable for backwash control valve heads requiring waterproof power and control wiring. Their multi-contact options support actuator, control, and feedback circuits within a single connector interface.
SP21 Series connectors provide secure cable-to-control-box connections for industrial NEMA enclosures. Their IP68 protection, larger cable compatibility, and multiple contact options make them suitable for outdoor control and power distribution systems.
Unique Features of SP21 Series Connectors
Selected SP21 Series configurations support rated current up to 30 A, providing a suitable connection option for equipment with higher power requirements.
Available with 2 to 12 contacts, including selected 5- and 6-contact configurations with different contact sizes for circuits requiring different current capacities.
Designed for reliable connections in outdoor, industrial, and moisture-exposed environments when properly assembled and mated.
Two cable OD ranges, 4.5–7.0 mm and 7.0–12.0 mm, provide flexibility for different cable constructions and larger cable requirements.
SP21 Series Connector FAQs
Some SP21 Series 5- and 6-contact connectors are available with different contact sizes and layouts. This allows the same contact count to meet different current and wiring requirements.
When selecting these versions, check the current and wire size for each circuit, not just the total number of contacts.
Not always. Selected 5- and 6-contact SP21 Series connectors combine larger and smaller contacts in one connector.
The larger contacts can be used for higher-current wires and the smaller contacts for lower-current circuits. Send us your wire sizes, current requirements, and pin assignment, and we can help select the right configuration.
Choose a cable receptacle for cable-to-cable connections. For an equipment or control-box interface, use a fixed or flange receptacle according to the mounting structure.
If the receptacle will be installed on a panel, confirm the panel cutout and mounting dimensions from the drawing before machining the enclosure.
SP21 Series connectors cover cable OD ranges of 4.5–7.0 mm and 7.0–12.0 mm, but the cable-entry components must match the actual cable size.
If you change the cable during a project, check the finished cable OD again. A different jacket thickness or cable construction may require a different cable-entry configuration to ensure proper clamping and sealing.
Yes, in some cases. If the existing connector has the matching mechanical interface, contact layout, and electrical configuration, you may only need to replace the plug or receptacle.
Send us the existing part number or clear photos of the connector and contact layout, and we can check the mating side before you order.
Not all of them. Two connectors having the same number of contacts does not necessarily mean they can mate.
This is especially important with 5- and 6-contact versions because different contact sizes and layouts are available. Always match the plug and receptacle by their complete contact configuration.
Yes. INTE-AUTO can supply SP21 Series connectors with customized cable assemblies.
You can specify the cable type, cable length, wire gauge, pin assignment, and opposite-end termination. We can also prepare the assembly according to your wiring drawing or existing sample.
Check more than the contact count. Compare the current and voltage, wire size, cable OD, panel cutout, mounting method, pin assignment, and available installation space.
If you do not know the existing connector model, send us clear photos, dimensions, drawings, or a sample. INTE-AUTO can check whether an SP21 Series connector is suitable for the replacement.
