false 0 https://www.bulgin.com

In the world of electronics, it’s hip to be square.

Reconnector_Connectors-1Rectangular connectors, also known as rectangular plugs, are one of the most popular and versatile connector shapes. Available in an array of configurations, these connectors cater to a range of power, signal, and data transmission requirements.

When it comes to establishing reliable electrical connections in various applications, rectangular connectors typically stand out as the simplest and most efficient solution.

This post delves into the details of multi-pin rectangular connectors, exploring their applications, differences, and the various options available at Bulgin.

Multi-Pin Rectangular Connectors

Silicone-sealed from dirt and moisture, Bulgin’s IP68-rated Rectangular Connector line offers reliable, rugged solutions for cable-to-cable applications in harsh environments.

The compact form factors are designed to handle a variety of signals for applications rated at different amperages:

  • Miniature — 7.5A
  • Standard — 13A
  • Automotive — 14A
  • Power — 25A

Various modifications to the line include enhanced seal retention, shrink boot adapters, welded flanges, terminating resistors, and Y-Type connectors.

Because these purchasing options may not be obvious at first, we’ll discuss each of these features in more detail.

Common Applications

Where do you find rectangular plugs deployed? Pretty much everywhere.

Bulgin’s rectangular connectors, molded from polybutylene with embedded polyamide glass-fiber reinforcements, provide premium, long-lasting interconnects that are widely used across several industries:

Marine – rectangular IP-68-rated plugs are suitable for cable-to-cable applications where reliable connections are required in harsh environments, even submerged in water. For example: unmanned surface vehicles, boat and yacht lighting, and GPS marine equipment.

Transport & Infrastructure 
– With a choice of enhanced sealed retention, Bulgin plugs are common in outdoor transportation applications such as traffic lights, lorry/truck LED lighting, and transport refrigeration.

– Maintaining reliable connections even through shocks and vibrations, rectangular plugs are seen in power diagnostics, agricultural pickers, and off-road vehicles.

Renewable Energy
 – miniature and standard outdoor connectors work well with solar light panels and solar battery enclosures.

Features and Options

Pin Count

Reconnector_Connectors_Pin-CountBuyers can choose rectangular connectors with varying numbers of contacts, with standard options of 2, 3, 4, 6, 8, or 12 poles. Determining the pin count for a project depends on the discrete number of signals needed for operation, plus some. Engineers often select additional pins for redundancy of important functions and the possibility of expanded features.

The pin conductive contacts at Bulgin are made of copper alloy with either nickel or gold plating.

px0101p02gy_2-1Pins and Sockets (Male/Female Configuration)

Pin-and-socket construction ensures a secure and polarized connection. The male (pin) and female (socket) configurations are sold separately rather than in a pair.

Welded Flanges

For devices requiring a more permanent or rugged connection, connectors with welded flanges are a useful option. The flange can then be bolted onto a rigid, heavy-duty casing.

Protective End Caps

To safeguard the connectors from damage when not in use or during product shipments, protective end caps that fit your pin-configuration are available as an add-on.

Shrink Boot Adapters

For even greater seal protection beyond the standard ingress prevention, a shrink book adapter can be installed over the cable and connector assembly before the connector is mated. Once in position, heat is applied uniformly around the adapter, causing it to shrink and conform tightly to the contours of the cable and connector. This process ensures a robust and secure seal, relieving strain, preventing accidental de-mating, and further shielding the connection from environmental factors.

Terminating Resistors (TER)

For better signal integrity and reduction of parasitic effects, an embedded terminating resistor (TER) inside the connector provides a convenient, space-saving, and reliable solution.

In TERs within rectangular multi-pin plugs, the resistor value should match the characteristic impedance of the CAN bus wiring. If the impedances don't match, some of the high-frequency signal will be reflected at the end of the bus.

The resistor value should be related to the trace impedance. Most of the time, the resistor value is the same as the trace impedance.


A useful added accessory to Bulgin connectors, a wedgelock harnesses wiring for improved contact retention and alignment. It also prevents de-mating, resisting tensile forces on wires up to 111 N. You can order wedgelocks that fit your gauge of wire as a separate item.

Wires and Crimping

Bulgin’s rectangular product line accommodates a range of standard wiring, based on the class of the connecter:crimping-tool

  • Miniature — 14-22AWG
  • Standard — 14-20AWG
  • Automotive — 13-22AWG
  • Power — 10-14AWG

Durability You Can Trust

Despite the wide variety, rectangular connectors at Bulgin have a few things in common. They are designed for robustness and durability even in extreme operating conditions. All products are durable enough to withstand extended use (100 mating cycles) and wide temperature fluctuations from -55° to +125°C (-40° to +125° for automotive-class plugs).

When selecting a rectangular connector, understanding the specific requirements of the application helps to narrow the buying options. Once the number of contacts, the protective features, and the general size of connection are determined, there’s a good chance there is a rectangular connector in the catalog to meet the need.

Need help on finding the right part? For specifications on Bulgin rectangular connectors, download our data sheet. For questions about any of Bulgin’s products, our knowledgeable technicians are here to help.

Do you have a question or a project enquiry that you'd like to talk to us about?