REMOTE MONITORING FOR RECTIFIERS, TEST POINTS AND BONDS with two-way communication and GPS-synchronized interruption

Building on the comprehensive monitoring capabilities of the RMU2, the RMU3 adds two-way communication for accurate, remotely controlled configuration and GPS-synchronized interruption of rectifiers. The RMU3 is a high reliability device engineered to control and monitor rectifiers, bonds and test points. The device provides GPS synchronized interruption functionality and is available in cellular or satellite communication configurations.

The field hardware consists of two primary components: a measurement terminal block (4-channel [compatible with MUX3 to expand to 16 channels] and 44-channel [RMU3-XL] options available) that is mounted inside the rectifier or a NEMA4 enclosure, and the antenna transceiver that is typically externally mounted. The RMU3 operates from a low voltage source such as a Class 2 transformer and has an internal battery backup system for short-term operation during power outages. Engineered for the lowest power consumption possible, the RMU3 is also suitable for TEG and solar applications. The RMU3 has integral high-energy surge suppression and provides unprecedented lightning immunity because there are no connections to electrical ground.

The RMU3 monitors and transmits nine channels of information – four high accuracy, galvanically isolated, AC/DC capable analog inputs are typically used to monitor volts, amps and/or 4-20mA signals from external equipment. An integral non-contact AC Line presence sensor can be used to determine if AC line voltage is present. An integral magnetic sensor can be used as a rectifier door sensor or tamper detection alarm. The RMU3 measures temperature and internal battery voltage and a user accessible switch can be configured to record site visit information. The RMU3 is also available with an optional “Measurement Recorder” which will capture analog readings every 6 hours and can store approximately 8 years of readings depending on your configuration.

Measurement data is wirelessly transmitted to the CorView Cloud Platform. CorView provides remote interruption control of the RMU3 equipped rectifier, manages all field data communications, maintains three years of measurement data, sends alarm exception and system performance emails, and controls password protected remote customer access. CorView is a highly secure environment that can be accessed using any web-enabled device as well as native iOS and Android apps. Measurement data is presented in an intuitive tabular format or graphical mapping display that color-codes abnormal measurement or site conditions for quick user interpretation. CorView can also provide near real-time email notification of abnormal measurement and alarm conditions.

Fast, simple installationThe compact, weather-proof RMU3 is designed for the measurement terminal to easily fit inside a rectifier cabinet or a NEMA4 enclosure with an external antenna that has been tested and proven in the most extreme applications – the system can typically be installed in under an hour.
Designed for high accuracy and resilienceExternal analog channels are high impedance and galvanically isolated with multistage lightning protection. AC rejection filters are utilized for DC measurements to provide maximum accuracy. Several voltage ranges to accommodate a wide range of sensors (current shunts, reference cells, and direct voltage measurement)
Intelligently engineered with additional functionality and expandabilityRMU3 platform has an AC Line Presence Sensor available to determine voltage is present, a magnetic sensor on enclosure doors that will alarm when unauthorized tampering occurs, an optional Measurement Recorder to capture analog readings, and a 4-20mA mode to receive signals from external equipment like the MOBILTEX TS1 temperature sensor. The MUX3 Channel Expansion Base Multiplexer allows for easy expansion with up to four RMU3-B bases to be connected to a single RMU3 antenna.  Expands channel capacity to a maximum of 16 channels.
CorView Compatible – Multi-tenant Advanced Cloud Platform with OpenAPI and SOC2 Compliance Engineered for the future on AWS to deliver the maximum security, scalability, open-compatibility and performance that will soon become system requirements for operators + eliminating issues when running “closed” legacy systems that restrict customers from accessible APIs
Multiple pre-defined configurationsThe RMU3 can be utilized at test points and bond monitoring applications, in addition to the more conventional rectifier, TEG and solar applications. AC mitigation systems can also be monitored with an optional AC current transformer.
Intuitive controls and configurationsThe RMU3 comes standard with an external “TEST” button and dual colour LEDs for manual controls. It can be easily programmed with our standard Programming Interface and a PC and can also be completed with a compatible iOS or Android-based mobile device and our available Bluetooth Interface.
Global communication capabilitiesAvailable with cellular or satellite communication capability, the RMU3 can transmit data from virtually any location. This helps improve the quality and frequency of data collection, while reducing the need for workers to undertake long, potentially dangerous trips, to remote sites.
Smart readings and transmissionsTo minimize airtime costs, the RMU3 stores four sets of periodic readings and then transmits all of those readings via four available factory-configured satellite or cellular data transmission plans. Irrespective of data plans, the RMU3 takes measurements every 6 hours, the device will immediately initiate a transmission when an alarm condition is detected. Alarms can be suppressed during interruption.
Built to withstand the toughest conditionsLightning, surge and overvoltage protection — intelligently designed with no earth ground bond, there’s NEVER been a requirement to purchase additional surge protection or “hardening” with MOBILTEX RMUs + the broadest operating temperature range (-40° to +60°C [-40° to +140°F]).
Intelligent, flexible installation options for power & interruption

Wide range of options available designed to optimize performance and lower costs plus included integral battery backup system powers the device for approximately 16 hours (RMU3-G) or 10 hours (RMU3-S) during power outages.


RMU3 Base – Environmental
Operating Temperature-40° to +70° C (-40° to +158° F)
Storage Temperature-45° to +80° C (-49° to +176° F)
Maximum Altitude5000 meters above sea level
Humidity0 to 100% RH non-condensing
RMU3 Base – Physical + Power
Weight200 grams (0.44 lbs)
Size135mm x 38mm x 38mm (5.3” x 1.5” x 1.5”)
Power SourceLPS or Class 2 CSA/UL approved (CSA 60950-1 or UL 60650-1)


RMU3 Antenna – Environmental
Operating Temperature-40° to +70° C (-40° to +158° F)
Storage Temperature-45° to +80° C (-49° to +176° F)
Maximum Altitude5000 meters above sea level
Humidity0 to 100% RH non-condensing
RMU3 Antenna – Physical + Power
Weight550 grams (1.2 lbs)
Size53mm x 77mm x 134mm (2.1” x 3.0” x 5.3”)
Power Source8.5 VDC nominal, supplied from RMU3-B

Documents & software

MOBILTEX CorTalk RMU3 ManualCorTalk RMU3 Manual v1.11PDF
CorTalk RMU3 Configuration Utility, Firmware and DriversRMU3 Install Pack v1.0.0.17ZIP
RMU3 Config Apple iOS AppDownload from iTunesLink
RMU3 Config Android AppDownload from Play StoreLink
CorTalk Full Install Pack v1.0.0.25Downloads ZIP fileZIP
LTE Swap Apple iOS AppDownload from iTunesLink
LTE Swap Android AppDownload from Play StoreLink
CorView Apple iOS AppDownload from iTunesLink
CorView Android AppDownload from Play StoreLink

Frequently asked questions

Can I use the rectifier taps to power the RMU3-B?

No. It is not recommended due to less electrical isolation. CSA/UL installations require a class 2 energy limited power source. Power your RMU3 from the AC mains with our custom transformer available from Mobiltex which has breakdown voltage of 5000VRMS for improved lightning immunity (typical is only 1500VRMS). Mobiltex Part Number: T01A42TR201

Do I connect one wire from the RMU power transformer to earth/functional/chassis ground?

No. Select the two appropriate color of wires required for your input voltage. Cap off the unused wires individually.

For example, when using the TR20VA020 Transformer (Mobiltex Part Number: T01A42TR201):
120VAC: Connect the black and white wires across the hot and neutral 120VAC lines
240VAC: Connect the black and orange wires across the hot 240VAC lines

What does a flashing green LED on the RMU3-B indicate?

When the multi-purpose LED is flashing green, it will depend if the device was recently transmitting:

  • If the RMU3 recently transmitted, the flashing green LED indicates it is waiting for an acknowledgement from CorView. Once the RMU3 receives the acknowledgment, the green LED will turn solid green.
  • If the RMU3 is not transmitting, the flashing green LED indicates that the most recent reading is outside of the programmed measurement limits (alarms)



TitleImageDescriptionSKU (s)
RMU3 Wiring Kit1 meter (3.2 ft) wiring harness, assorted crimp terminals, cable ties, adhesive tie mounts. The components of this kit are typically used to interconnect the measurement signals from the rectifier, test point or bond to the RMU3-B.Mobiltex P/N A20103RMU30
Class 2 Transformer120 or 230 VAC to 12VAC 20VA. Lightning resistant 5,000V insulation. Foot or ½” conduit hub mount.Mobiltex P/N T01A42TR201
External 3:1 Voltage DividerRequired for applications that measure greater than 150VDC or 105VAC. Typically used when actual AC line voltage (110/120 or 220/230 VAC) measurement is desired.Mobiltex P/N A01160RMU21
Solid State AC Relay— 24-280 VAC RMS 50 Amps max0-8A = No Heatsink
8-50A = Needs HE-54
Mobiltex P/N K0513245010
Solid State AC Relay— 24-280 VAC RMS 110 Amps max0-8A = No Heatsink
8-60A = HE-54
60-110A = HE-90
Mobiltex P/N K0513211010
Solid State AC Relay— 48-530 VAC RMS 50 Amps max0-8A = No Heatsink
8-50A = Needs HE-54
Mobiltex P/N K0513285010
Solid State AC Relay—3 phase, 48-530 VAC RMS 50 Amps max0-4A = No Heatsink
4-30A = HE-90
Mobiltex P/N K05232R5016
Small Heatsink (HF92B)For Solid State Relay (HF92B)Mobiltex P/N X0301292B80
Medium Heatsink (HE-54)For Solid State Relay (HE-54)Mobiltex P/N X030120HE54
Large Heatsink (HE-90)For Solid State Relay (HE-90)Mobiltex P/N X030320HE90
Solid State DC Relay (DCR1)0-60 VDC 50 Amps max
(Complete unit including heatsink)
Mobiltex P/N A15060255C1
Solid State DC Relay (DCR1+)0-100 VDC 100 Amps max
(Complete unit including heatsink)
Mobiltex P/N A15060255C2
Mercury Relay240 VAC @ 100 A, 48 VDC @ 100 A, 125 VDC @ 50 AMobiltex P/N K07111NC12D
TitleImageDescriptionSKU (s)
1-meter Interconnect Cable1-meter (3.2 ft) long interconnection/extension cable. Comes with molded waterproof connectors.Mobiltex P/N W16400RMU03
3-meter Interconnect Cable3-meter (9.8 ft) long interconnection/extension cable. Comes with molded waterproof connectors.Mobiltex P/N W16400RMU01
8-meter Interconnect Cable8-meter (26.2 ft) long interconnection/extension cable. Comes with molded waterproof connectors.Mobiltex P/N W16400RMU02
RMU1/2/3-BT Programmer KitUniversal programming kit for RMU1, RMU2, and RMU3 devices. Includes RMU1/2/3 base programmer (A1506033101), RMU1ADP (A1506033001), Lithium-Ion battery pack, soft case and USB stick with programming software. Capable of Bluetooth communications with a phone/tablet. Can also be used with a PC through the USB connection.Mobiltex P/N A20A0333101
RBT1 Bluetooth Interface CableAllows programming of RMU3 using a Bluetooth Smart equipped smart phone or tablet.Mobiltex Part Number A1506032101
TitleImageDescriptionSKU (s)
RMU3 Universal Mounting BracketAluminium bracket, pipe clamp, and bracket mounting screws. This kit can be used for installations that require the RMU3-G or RMU3-S to be mounted in a configuration other then the top of the rectifier lid or applications using standard ½” NPT electrical fittings. This kit allows mounting on either vertical or horizontal surfaces as well as vertical pipe or pole installations.Mobiltex P/N A20103RMU31
4-20mA Transducer Shunt KitKit of 4 precision 250 ohm resistors for installations using 4-20mA measurement transducers. Not applicable to RMU3X-B.Mobiltex P/N A20003RMU21
MUX3 Channel Expansion Base MultiplexerAllows up to four RMU3-B bases to be used with a single RMU3 antenna.  Expands channel capacity to a maximum of 16 channels.  Bases and interconnect cables are purchased separately.Mobiltex P/N A1506030901
DRT1 Dual Relay Timer for RMU3Allows taking advantage of both Mercury and Solid-State relays’ strengths.

Use a Mercury Relay to be the main conductive path in normal functioning while allowing an SSD to take over during interruptions’ period.

The Mercury Relay will close again after 30 seconds without interruptions.

Mobiltex P/N A1506035601
Cathodic Protection Monitoring Pipeline scene graphic illustrated in an isometric view Cathodic Protection Monitoring Pipeline scene graphic illustrated in an isometric view


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