Model 29 Frequency Monitor has a display that shows the frequency with an accuracy of +/- 0.5%. The display is updated every second and re-initialized every 30 seconds. This unit has a user selectable relay option for High-Low or DPDT. It can also be user-selected to energize on fault or de-energize on fault. The user can select automatic or manual restart on the Model 29. The SG version of the Model 29 has silver with gold flash contacts for low current applications Model 29 Frequency Monitor can be restored to factory defaults.. Specifications: Certifications: UL (C and US); Contacts: SPDT(2); Mount: DIN, Surface Mount; VF Function: Frequency Monitor; Voltage Range: 80-550VAC