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When troubleshooting a hydraulic system, it’s often discovered that the problem is not hydraulic at all, but rather electrical. And in the realm of electronics, connectors are notorious for being sources of malfunctions. Worse yet, when bad connections occur intermittently, it seems like they’re working fine when you check them; then they act up again when you move on to check something else.

Brian Smith, owner of SDSi LLC, came up with a patented solution that makes it easy to see if power is getting through. His U.S. patent covers the 2PLC connector (male plug and molded cable assembly), which is compatible with Deutsch 2-pin DT04-2P, Amphenol AT02-2P, and compatible receptacles often molded into electrohydraulic solenoid valves and switches.

Smith realized the value of proprietary LED-indicating connectors from OEMs, but was frustrated to learn the feature was not offered in industry-standard connectors. He began developing the 2PLC connector in 2010 and subsequently acquired IPX9K certification. The connector not only visually indicates continuity, but it withstands the harsh environmental conditions typically encountered with off-highway hydraulic systems. Potential applications include construction, mining, forestry, oilfield, agricultural, and waste-handling equipment.

More recently, Smith introduced the 4PLC, a 4-pin lighted connector. Both connectors carry a 12/24-V dc, 13-A rating. They feature a thermoplastic housing and elastomer sealing gasket to exclude dirt and moisture, plus two-part polymer epoxy plug potting to further prevent moisture wicking and failures from shock  or vibration. Custom cable lengths and harness assemblies with up to six plugs are made to order.

For more information, call (817) 449-7642, email sales@2plconline, or visit

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