On the 1st January 2012 the 17th Edition wiring regulations were amended to include the need for transient protection for the first time. The 1st amendment now requires that consideration should be given to protection against Voltage and Electromagnetic disturbances. In many cases the use of surge protection devices (SPD) is now required. The 17th Edition handbook shows in appendix 16 the various types of power distribution systems along with how SPD should be connected. As each type of power distribution system requires a slightly different type of transient protection we have devised the table below to indicate which Roxburgh item should be used and the corresponding Farnell stock code
| 17th Edition 1st amendment surge protection devices | |||||
| Farnell Part | Roxburgh Item | System | Supply | Appendix 16 Diagram | Type1/Type2 |
| DVSC400454TNS | TT connection Type 1 | 3 Phase + Neutral | 16A2 | Type 2 | |
| 1843214 | DVSC400454TT | TT connection Type 2 | 3 Phase + Neutral | 16A3 | Type 2 |
| 1843213 | DVSC400453TNC | IT | 3 Phase | 16A4 | Type 2 |
| 1843207 | DVSB400654TNS | TN-C-S | 3 Phase + Neutral | 16A5 | Type 1 |
| DVSC400454TNS | TN-C-S | 3 Phase + Neutral | 16A5 | Type 2 | |
| 1843211 | DVSC275452TNS | TN-C-S | Single Phase | 16A5 | Type 2 |
Attachments:
 | SPD17thEdition(1).pdf |