Sinetamer RM-ST120 Parallel 380V – 480V Transient Voltage Surge Supressor

The SineTamer© RM series of units blends outstanding high-energy “impulse” suppression with excellent “ring-wave” transient protection utilizing our Frequency Attenuation Network®. This durable device is intended for general purpose and sensitive/critical load applications. The RM-ST120 is typically installed at small service entrances up to 800 amps, distribution and sub-distribution panels. The circuit design of the RM series does not shunt transients to ground, but utilizes discrete mode circuitry to create a near equipotential bond amongst all conductors to dissipate surge energy. The units are all bidirectional enabling them to suppress any surges from ground between any connected phases. This economical device has features that are not available in devices costing many times its price. Its compact size makes installation a breeze. Maintenance Free operation and 15 Year Unlimited Free Replacement Warranty provide peace of mind. Standard unit is Type 2 10kA UL Nominal Discharge Current, Optional Type 220kA IN is available


  • Application


    Designed for use at ANSI/IEEE Categories C, B and A with susceptibility up to medium exposure levels. Designed to protect sensitive/critical loads fed from distribution panels, branch panels and/or individual equipment panels.

Technical Specification

Parallel connected, transient voltage surge suppressor device utilizing both high-energy
handling and Frequency Attenuation Network® circuitry for virtual elimination of impulse
and ring wave type transients. (tracking and monitoring the AC sine wave)
High strength ABS Plastic, NEMA 4 rated enclosure.
3/4” conduit fitting (internally threaded) and external mounting feet.
Connection Method
#10 stranded wire.
Circuit Design...
Parallel connected, internally fused, hybrid design incorporating all mode protection, and
utilizing our encapsulated design to provide improved durability.
...Circuit Design
All suppression circuits are
encapsulated in our exclusive compound to assure long component life and complete protection from the environment and/or vibration.
Protection Modes
L-N, L-L (Normal Mode), and L-G, N-G (Common Mode). (Seven discrete modes)
Input Power Frequency
50-60Hz constant
EMI/RFI Noise Attenuation
30dB Max. from 1kHz to 10MHz
Circuit Diagnostics
Super Bright LED, 1 per phase, normally on.
Circuit Interrupt
External and internal (see installation instructions for details).
Component Level Thermal and Board Level Current Fusing
kAIC Rating
200 kAIC when installed according to installation instructions
RM-STB = Type 2 20kA IN Type 1 available – contact factory for proper model number.