{"product_id":"siemens-6es7421-7dh00-0ab0-sm-421-16di-24-60v","title":"Siemens 6ES7421-7DH00-0AB0 SIMATIC S7-400 SM 421 16DI 24-60V UC PLC I\/O Module","description":"\u003cp\u003eThe Siemens 6ES7421-7DH00-0AB0 SIMATIC S7-400 SM 421 module provides 16 individually isolated digital inputs rated 24-60 V UC, accepting both AC and DC field signals. Input delay is fixed to four selectable steps from 0.5 to 20 ms, and the module reports diagnostic alarms plus hardware interrupts to the CPU when parameterized. Wire-break detection triggers above 0.7 mA.\u003c\/p\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput current – from backplane bus 5 V DC, max.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e150 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePower loss – Power loss, typ.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e8 W; 3.5 W (24 V DC); 6.5 W (48 V DC); 8.0 W (60 V DC)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDigital inputs – Number of digital inputs\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e16\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDigital inputs – Input characteristic according to IEC 61131\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003esimilar to IEC 61131-2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eNumber of simultaneously controllable inputs\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e16\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput voltage – Type of input voltage\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eAC\/DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput voltage – Rated value (UC)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e24 V; 24 V UC to 60 V UC (47 ... 63 Hz)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput voltage – for signal 0\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e-6 to +6 V DC\/ 0 to 5 V AC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput voltage – for signal 1\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e15 to 72 V DC; -15 to -72 V DC; 15 to 60 V AC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput current – for signal 1, typ.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e4 mA; 4 to 10 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003efor standard inputs – parameterizable\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003efor standard inputs – Rated value\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e0.5 ms; 0.5 \/ 3 \/ 10 \/ 20 ms\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eEncoder connection – Fixed current limitation for wire-break monitoring, min.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e18 kΩ; 18 kohms: Rated voltage 24 V (15 to 35 V); 39 kohms: Rated voltage 48 V (30 to 60 V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eEncoder connection – Fixed current limitation for wire-break monitoring, max.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e56 kΩ; Rated voltage 60 V (50 to 72 V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCable length – shielded, max.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1 000 m\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCable length – unshielded, max.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e600 m; 600 m: 3, 10, 20 ms; 100 m: 0,5 ms\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eConnectable encoders – 2-wire sensor\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eConnectable encoders – permissible quiescent current (2-wire sensor), max.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e0.5 mA; 0.5 to 2 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInterrupts\/diagnostics\/status information – Diagnostics function\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes; Parameterizable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eAlarms – Diagnostic alarm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes; Parameterizable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eAlarms – Hardware interrupt\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes; Parameterizable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDiagnoses – Diagnostic information readable\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes; possible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDiagnoses – Wire break\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes; I\u0026gt; 0.7 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDiagnostics indication LED – Status indicator digital input (green)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePotential separation digital inputs – between the channels\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePotential separation digital inputs – between the channels, in groups of\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePotential separation digital inputs – between the channels and backplane bus\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eIsolation – Isolation tested with\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1 500 V AC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDimensions – Width\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e25 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDimensions – Height\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e290 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDimensions – Depth\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e210 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eWeights – Weight, approx.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e600 g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch2\u003eSelection Notes\u003c\/h2\u003e\u003cp\u003eThis variant accepts 24-60 V on AC or DC (UC) field wiring, wider than a fixed 24 V DC-only input, so it fits mixed AC-driven and DC-driven field devices without a separate module. Each channel is isolated individually (groups of 1) rather than in larger blocks, which allows different signal sources per channel without cross-coupling. Input delay is fixed to four steps – 0.5, 3, 10 or 20 ms – suited to slower AC-driven field contacts rather than high-speed DC counting. Wire-break detection triggers above 0.7 mA, useful where open-wire detection on the field circuit matters.\u003c\/p\u003e","brand":"Siemens","offers":[{"title":"Default Title","offer_id":53960591147291,"sku":"6ES7421-7DH00-0AB0","price":686.34,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0903\/7722\/4475\/files\/siemens-6es7421-7dh00-0ab0-sm-421-digital-input-module.png?v=1789782176","url":"https:\/\/stoklink.com\/products\/siemens-6es7421-7dh00-0ab0-sm-421-16di-24-60v","provider":"Stoklink","version":"1.0","type":"link"}