Heavy-Duty Connector Selection Guide
Six steps to the right insert, housing and accessories — with a series comparison, an insert-to-housing table and FAQs.
- 01
Define the circuits
Count power and signal circuits, note the current and voltage of each, and whether you need PE, data or pneumatic lines.
- 02
Choose the insert series
Up to 16 A: HA / HE. Many circuits: HEE, HD, HDD. High current: HSB, HK. Mixed power, signal and data: HM modules. Tight space: HQ. See the comparison table below.
- 03
Choose the termination
Field wiring: screw. Volume assembly or vibration: spring. Harness production and high-density inserts: crimp (needs crimp contacts and a crimping tool).
- 04
Match the housing size
The insert size determines the housing size — e.g. HE-024 fits H24B and HA-010 fits H10A. See the matching table below.
- 05
Pick the housing style
Hood: side or top entry, standard or high construction. Base: bulkhead, surface mount or cable-to-cable. Locking: single or double lever.
- 06
Select entry thread and gland
Choose M20, M25, M32 etc. and a matching cable gland by cable diameter; PG threads are available for replacements.
Insert Series Comparison
Data taken from each series’ technical data in the SZXBS catalog; see each part page for details.
| Insert | Rated current | Rated voltage | Poles | Termination |
|---|---|---|---|---|
| HA Miniature Inserts | 10–16A | 250–400V | 3–16 | Screw termination / Spring termination |
| HE Standard Inserts | 10–16A | 250–500V | 4–64 | Screw termination / Spring termination |
| HEE High-Density Inserts | 16A | 500V | 10–72 | Crimp termination |
| HD Ultra-High-Density Inserts | 10A | 250V | 7–64 | Crimp termination |
| HDD Ultra-High-Density Inserts | 10A | 250V | 24–108 | Crimp termination |
| HSB 35 A High-Current Inserts | 35A | 690V | 4–8 | Screw termination |
| HK Combined High-Current Inserts | 1–100A | 50–830V | 0–36 | Crimp termination / Axial screw termination / Screw termination |
| HM Modular Connectors | 1–300A | 32–1000V | – | Crimp termination / Axial screw termination / Screw termination / Spring termination / Spring termination (quick-connect) |
| HQ Compact Inserts | 6.5–100A | 50–830V | 1–12 | Axial screw termination / with heat-shrink sleeve / Crimp termination |
Insert-to-Housing Matching
FAQ
What parts make up a heavy-duty connector?
A heavy-duty connector set usually consists of a male and a female insert, a hood and a housing (base), and contacts. Crimp inserts need separate crimp contacts; screw and spring inserts have the terminals built in. Choose the insert first (poles, current, voltage), then pick the hood and housing that fit the insert size.
Are SZXBS products interchangeable with other brands of the same size?
SZXBS inserts and housings follow the industry-standard outline and mounting dimensions, and part numbers map to the common sizes (for example, an HE-024 insert fits an H24B housing). Before switching in volume, we recommend checking the dimension drawings or testing samples.
What is the difference between IP65 and IP67?
Both are fully dust-tight (first digit 6). The "5" in IP65 means protection against water jets from any direction; the "7" in IP67 means protection against temporary immersion (1 m for 30 minutes under the standard test). IP65 suits most indoor and sheltered outdoor equipment; choose IP67 or higher where water can pool or equipment is hosed down. An SZXBS HE-024 sample was tested by an independent lab to GB/T 4208-2017 (equivalent to IEC 60529) and met IP65.
Screw, spring or crimp termination — which should I choose?
Screw termination needs no special tools and suits field wiring and maintenance. Spring (cage-clamp) termination is fast and vibration-resistant, good for volume assembly. Crimp termination requires a crimping tool, gives a reliable compact connection and is standard for high-density inserts and harness production.
What is the difference between PG and M cable-entry threads?
PG is the traditional German conduit thread; M is metric (e.g. M20, M25, M32). New designs generally use metric threads, while PG is mainly for replacing existing equipment. The housing entry thread must match the cable gland, and the gland is then chosen by the cable outer diameter.
How can I get samples, quotes and CAD drawings?
Send us the part numbers and quantities by phone or e-mail. Standard parts are usually in stock and samples ship quickly. Dimension drawings are shown on every product page, and the full PDF catalog is free to download from the Downloads page.