The LAD8N026 is a TeSys Deca auxiliary contact block — two normally-closed (2NC) contacts that mount on the side of a contactor or starter. It's the kind of part you grab when you need a spare NC feedback loop for a safety circuit or a status signal back to the PLC, and you need it to fit the existing TeSys Deca footprint without reworking the panel. Rated 10 A conventional free-air thermal current (Ith) at 60 °C, with an insulation voltage (Ui) of 690 V per IEC 60947-5-1 and 600 V per UL/CSA. That means it handles the control-circuit loads you'd expect — pilot duty, relay coils, contactor pick-up — without derating surprises in a warm enclosure. The NC contacts are mechanically linked with a 1.5 ms non-overlap time on both energisation and de-energisation — no momentary bridging between NC and NO circuits. That matters for safety interlocks where you need a guaranteed break before the make.
Rated operational current (Ie) varies by duty: 6 A at 120 V AC-15 (typical for solenoid valves and contactor coils), 1.04 A at 690 V AC-15, 0.55 A at 125 V DC-13, and 0.1 A at 600 V DC-13. The AC-15 rating is the one you'll lean on for most control-circuit switching — it's the standard for electromagnetic loads. The DC-13 numbers are lower because DC arcs are harder to extinguish; if you're switching DC relay coils at 125 V, the 0.55 A limit governs. Making capacity is 140 A AC and 250 A DC per IEC 60947-5-1 — that's the peak inrush the contacts can close onto without welding. Short-time ratings (100 A for 1 s, 120 A for 500 ms, 140 A for 100 ms) cover brief overloads like capacitor bank or lamp inrush. Minimum switching capability is 5 mA at 17 V — so it'll reliably switch dry contacts or low-level PLC inputs without needing a wetting current. That's a detail that trips people up on cheaper blocks.
Side-mounts onto TeSys Deca contactors and reversing starters. Occupies a 12.5 mm wide slot — that's one module width on a DIN-rail assembly, so it doesn't eat up panel space. Depth is 71.3 mm, height 72 mm; stays within the envelope of the base contactor. Terminals accept lugs-ring connections with an 8 mm outer diameter. Tightening torque is 1.7 N·m with a flathead, Philips #2, or Pozidriv #2 — any electrician's screwdriver will do. No special tools. IP20 finger-safe protection per IEC 60529 — fine for enclosed panels.
Standards compliance covers EN/IEC 60947-5-1, UL 60947-5-1, CSA C22.2 No 60947-5-1, plus IEC 60335-1 Clause 30.2 and UL 60335-2-40 Annex JJ for appliance applications. That's the full set for industrial control panels and HVAC equipment destined for North America or Europe. Mechanical durability is 30 million cycles — essentially lifetime for a control-circuit contact block in normal service. No wear-item replacement schedule needed.