At the beginning of this year we introduced to you the Tank Cloud MND (short for Modbus Network Display). To review, this display unit connects to a Modbus network to provide local tank level readings. You can program it as a sniffer – displaying readings by “eavesdropping on the conversation” between the slave units and the master – or you can use it as the master and poll the slaves sensors on the Tank Cloud network.
Today we would like to tell you a little more about the MND as a master.
Using the MND as a master is ideal for situations where you do not require remote monitoring and no other master is present, such as a PLC. Unlike the LOE ultrasonic sensor or the RST module, the MND is for local display applications only and cannot transmit a signal over the Internet.
One of our customers is using the MND as a master to display levels for multiple tanks on its trucks. Each truck is outfitted with about 4 tanks on the back and is equipped with one of our Tank Cloud MPX-E sensors. Each of these sensors is wired together via a daisy chain to form a network. Meanwhile the MND is mounted in the cab. This way, the truck operator is able to access tank levels while in the cab.
One of the most exciting ways you can use the MND as a master is to share battery power with a Tank Cloud sensor to create a self-contained monitoring system. You can do this by setting the first relay (T1) to “on” and configuring a short Auto-Off timer. Then all you will have to do is push the power button on the MND to wake the system. The MND will automatically poll the sensor to give you a reading. Finally, the Auto-Off will trigger and shut off the system to save battery life.
The same customer mentioned above is also using the MND master in this configuration in other situations. The power-sharing feature has allowed it to move its tanks from location to location without the hassle of finding a nearby power source. This mobility factor gives it a unique advantage.
The best part of this set up is that it can be used for any of our Tank Cloud Modbus RTU sensors: the MNU Modbus Network Ultrasonic, the PT-400 Heavy Duty Intrinsically Safe Pressure Transducer, the PT-500 Submersible Pressure Transducer, and any of our Explosion Proof Magnetostrictive MPX Level Transmitters.