Safety speed relay modulesAutomationDirect has added two Dold safety speed relay modules to its line of safety products. According to the company, these two models are characterized by:


  • A speed monitor relay module that is designed to monitor two sensor inputs that are detecting rotating targets on a motor shaft.
  • Features two-channel operation and can be used for standstill and overspeed monitoring of three-phase motors.
  • When used as a standstill monitor, a switch point is set just above the “safe” or normal operating speed; when motor speed rises above this setting, the relay opens to protect against motor damage.
  • Has an adjustable impulse-per-minute (IPM) range of 10 to 20,000 IPM, LED status indicators, two PNP sensor inputs and two normally-open and one normally-closed positive-guided contacts.
  • Available for 24VDC, 120VAC and 230VAC supply voltages.


  • A standstill monitor relay module that provides safe standstill detection on single-phase and three-phase motors (up to 690V) by monitoring remanence voltage without external sensors.
  • Designed with broken wire detection and provide three normally-open and one normally-closed positive-guided safety contacts.
  • Available in adjustable 20 to 400mV and 0.2 to 4V voltage response ranges, they are equipped with LED status indicators and adjustable time delay; semiconductor outputs monitor relay state.
  • Available for 24VDC, 120VAC, and 230VAC supply voltages.