EPCOS (TDK) have a variety of protective devices, such as Varistors (including Leaded and Housed Varistors, Block and Strap Varistors, Surface Mount Disk Varistors, MultLayer Varistors), Current Limiters (NTC Inrush Current Limiters, or ICLs), Thermistors (Surface Mount NTC Thermistors, PTC Thermistors) and more.
Each part numbering structure is slightly different, with examples shown below. Using the breakdown, you can identify the Product Group, Operating Voltage, Tolerance, Lead Configuration and Packaging.
Leaded Housed Varistors
Manufacturer Part Number: B72210XXXXXXXXX, such as B72210S2271K10
Block and Strap Varistors
Manufacturer Part Number: B72240XXXXXXXXX such as B72240B0271K001
Surface Mount Disk Varistors
Manufacturer Part Number: B726XXXXXXXXXXX, such as B72650M0110K072
Manufacturer Part Number: B724XXXXXXXXXXX, B725XXXXXXXXXXX, B727XXXXXXXXXXX, such as B72510T0250K062
NTC InRush Current Limiters
Manufacturer Part Number: B57XXXXXXXXXXXX, such as B57236S0100M051
Surface Mount NTC Thermistors
Manufacturer Part Number: B57XXXXXXXXXXXX, such as B57321V2103J060.
Manufacturer Part Number: B59XXXXXXXXXXX, such as B59421A0085A062