Siemens 6FQ2421-0AE is an Iskamatic B VD11 module described as a power supply diode coupler for Siemens Iskamatic safety systems. The part is cross-listed as 6FQ2421-0AE and 6FQ24210AE, confirming its identity within the VD11 Iskamatic family. Distributors and marketplaces show the device available as a used or surplus item under this part number, with listings from Paebra, Maaslos-Guenstig, and eBay platforms. Descriptions consistently label it as a VD11 Iskamatic power supply diode coupler, aligning with Siemens’ older Iskamatic B safety equipment used for diode‑coupled signaling in safety circuits.
