Relay Specialties, Inc. - TimeMark Corporation - Products - Special Controls

Monitors True Motor Power (volts x current x power factor)
Detects Motor Overload or Underload
Operates on 120 or 240VAC,Single-phase or 3-phase
Built-in Trip and Restart Delay Options

The Model 421 Over/Under Motor Load Monitor detects an overload or underload condition on all types of running motors: conveyer motors, elevator motors, mixer motors, submersible pumps, etc.

This Monitor detects the actual power used (voltage x current x power factor) and is more sensitive than simple current monitors. The 421 can be used with single phase motors or, using the Model 276C current transducer, with three-phase motors. Matching CT’s allow the Model 421 to be used with most motor sizes.

Optional trip and restart delays are provided.

Specifications

Model	421
Input Voltage Range	100-130VAC or 200-250VAC
Frequency	50/60Hz
Power Consumption	0.5 VA max.
Nominal Current	2.5 amps
Minimum Current	0.25 amps
Current Adjustment	0 - 5 amps x PF
Current Output	4-20mA for chart recorders
Repeat Accuracy	1 % (fixed conditions)
Output	SPDT 10A at 240VAC resistive
Expected Relay Life	Mech: 10 million operations Elec: 100,000 operations at rated load
Trip Delay	OFF or 0.3 to 180 seconds
Restart Delay	OFF or 0.1 to 4 hours
Indicators	Red LED: Overload or Underload; tripped Yellow LED: Restart timing
Transient Protection	2500V for 10ms
Operating Temp	- 20° to 131° F
Humidity Tolerance	97% w/o condensation
Enclosure Material	ABS plastic
Weight	1 lb.
Agency Approvals	UL Listed to US and Canadian safety standards CSA Certified

Downloads

Document	File Type	File Size	Download
Model 421 Datasheet	PDF	aaa KB