{"product_id":"siemens-6es7421-7bh01-0ab0-sm-421-16di-24vdc","title":"Siemens 6ES7421-7BH01-0AB0 SIMATIC S7-400 SM 421 16DI 24V DC PLC I\/O Module","description":"\u003cp\u003eThe Siemens 6ES7421-7BH01-0AB0 SIMATIC S7-400 SM 421 module provides 16 isolated digital inputs rated 24 V DC, meeting IEC 61131 Type 2 input characteristics. Two isolated encoder supply outputs with electronic short-circuit protection are built in, and the module reports diagnostic alarms plus hardware interrupts to the CPU. Input delay is parameterizable from 3 microseconds to 3 ms per channel.\u003c\/p\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLoad voltage L+ – Rated value (DC)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e24 V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLoad voltage L+ – permissible range, lower limit (DC)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e20.4 V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLoad voltage L+ – permissible range, upper limit (DC)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e28.8 V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLoad voltage L+ – Reverse polarity protection\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput current – from supply voltage L+, max.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e120 mA\u003c\/td\u003e\n\u003c\/tr\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\u003e130 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eEncoder supply – Number of outputs\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eEncoder supply – Type of output voltage\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eL+ (-2.5 V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eEncoder supply – Short-circuit protection\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes; Electronic\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eEncoder supply – additional (redundant) feed\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes; possible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOutput current – Rated value\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e120 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOutput current – permissible range, lower limit\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e0 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOutput current – permissible range, upper limit\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\u003e5 W\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\u003eType 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\u003eDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput voltage – Rated value (DC)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e24 V\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-30 V DC to +5 V DC\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\u003e11 V DC to 30 V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput current – for signal 0, min.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e6 mA; \u0026lt; 6 mA\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\u003e6 mA; 6 to 8 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput delay (for rated value of input voltage) – Input frequency (with a time delay of 0.1 ms), max.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e2 kHz\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 – at 0 to 1, min.\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e3 µs; 0.05 \/ 0.1 \/ 0.5 \/ 3 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\u003e10 kΩ\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\u003e18 kΩ\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; 1 000 m: 3 ms, 70 m: 0.5 ms, 30 m: 0.1 ms, 30 m: 0.05 ms\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 ms; 50 m: 0,5 ms; 20 m: 0,1 ms; 20 m: 0,05 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\u003e3 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\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDiagnoses – Monitoring the supply voltage\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes\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 \u0026lt; 1 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDiagnostics indication LED – Rated load voltage PWR (green)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes; Per group\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDiagnostics indication LED – internal fault INTF (red)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDiagnostics indication LED – external fault EXTF (red)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes\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\u003e8\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\u003e500 V DC\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\u003eThe input delay is parameterizable from 3 µs up to 3 ms, so the same module handles fast counting signals – up to 2 kHz at the 0.1 ms setting – and slower contact inputs that need debounce filtering. Two built-in, short-circuit-protected encoder supply outputs remove the need for a separate 24 V sensor supply, and the optional redundant feed keeps inputs live if one supply channel fails. Channels are isolated in groups of 8, so mixing different 24 V DC signal sources across the 16 inputs is only possible in two-group blocks, not per individual channel.\u003c\/p\u003e","brand":"Siemens","offers":[{"title":"Default Title","offer_id":53960590950683,"sku":"6ES7421-7BH01-0AB0","price":1055.39,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0903\/7722\/4475\/files\/siemens-6es7421-7bh01-0ab0-sm-421-digital-input-module.png?v=1789782170","url":"https:\/\/stoklink.com\/products\/siemens-6es7421-7bh01-0ab0-sm-421-16di-24vdc","provider":"Stoklink","version":"1.0","type":"link"}