Glossary of Terms

Keywords: Terms, sensors, gateways, software


This is a glossary of frequently used terms and phrases with their definitions.

Alert (Notification) See also “Notification”:  An email, SMS, or voice message indicating a sensor has crossed a user-set threshold or an event has occurred.

API (Application Programming Interface): The interface specifies how some software components should interact with each other.

APN is dual use dependent on context:

APN (Access Point Node): Radio module used in gateways to facility communication with a sensor network.

APN (Access Point Name): is the name of a gateway between a GPRS, 3G or 4G mobile network and another computer network, frequently the public Internet.

Aware State: The aware state is a mode the sensor can be configured to enter when specific thresholds are exceeded. This allows the sensor to operate at higher power consumption only when near critical conditions of the application you’re monitoring.

CGW (Cellular Gateway ): Gateway that uses the cellular infrastructure to communicate with monitoring platform such as

Configuration Terms (Sensors):


  • Interval: How often the sensor communicates with the gateway if no activity is recorded.
  • Sensor Name: The unique name given to this particular sensor for easy identification.


  •  Activate when:  Determines which reading of the sensor will trigger the Aware State.
  • Active Between: The time of day the sensor is actively working. No communication will take place while the sensor is hibernating.
  • Assessments per Heartbeat: How many times between heartbeats a sensor will check measurements against its thresholds to determine whether it will enter or remain in the aware state. (In relation to the sensor heartbeat, if the sensor HB is at 10 minutes and the APH is at 10, the sensor will assess conditions against the parameters once a minute. If the HB is at 10 and the APH is at 20, it will assess about every 30 seconds. If the HB is at 10 and the APH is at 250, then the sensor will assess the conditions at its maximum frequency of 1 second. )
  • Aware State Buffer: A buffer which prevents the sensor from bouncing between Standard Operation and Aware State when the assessments are very close to a threshold. 
  • Aware State Heartbeat: How frequently the sensor transmits data to the gateway while in the aware state.
  • Display As: Set the label for the data type (i.e. Fahrenheit vs. Celsius).
  • Failed transmissions before link mode: The number of transmissions the sensor sends without response from a gateway before it goes into Link mode.
  • Heartbeat Interval: How often the sensor transmits data to the gateway if no out of threshold activity is recorded.
  • Hysteresis: A buffer to prevent the sensor from bouncing between standard operation and the aware state.
  • Maximum Threshold: Any assessment above this value will cause the sensor to enter the “Aware State”.
  • Minimum Threshold: Any assessment below this value will cause the sensor to enter the “Aware State”.
  • Sensor is on: The time of day the sensor is actively working. No communication will be sent while the sensor is hibernating.
  • Sensor Name: Theunique name given to this particular sensor for easy identification.
  • Show Dew Point: Includes the dew point as a piece of information to the data to be displayed.
  • Synchronize: In small sensor networks, the sensors can be set to synchronize their communications. A sensor marked “Yes” for synchronize, does so with UTC time.  So it will set itself to communicate at Midnight UTC then base it's heartbeat on that, rather than on when the battery is inserted. The default setting “Off” allows the sensors to randomize their communication therefore maximizing communication robustness. Setting this will synchronize the communication of the sensors.
  • Time Frame: Time frame in minutes to evaluate
  • Time to Re- Arm (seconds): The time in seconds after a triggering event that the sensor will wait before re-arming itself.
  • Use Aware State: Any assessments outside of these user-set values will cause the sensor to enter the Aware State.
  • Use this sensor through a repeater: Check this box if the sensor will be used in conjunction with a repeater. (Default status is unchecked).   Note: Only applies to sensors with firmware released prior to
  • Data Export Definitions:
  • Alert: Boolean (True/False) indicating if this reading triggered a notification to be sent from the system.
  • Battery: Estimated life remaining of the battery.
  • Data: Raw data as it is stored from the sensor.
  • Date: The date the message was transmitted from the sensor.
  • GatewayID: The Identifier of the gateway that relayed the data from the sensor.
  • MessageID: Unique identifier of the message in the database.
  • Plot Value: Data presented with any transforms applied but without additional text labels.
  • Received Signal: The signal strength measured in RSSI (From Wikipedia: In telecommunications, Received Signal Strength Indicator (RSSI) is a measurement of the power present in a received radio signal.)  This is the number that is used to calculate the “Signal Strength” column which we show as a percentage.  For certain engineers this column is more useful than the calculated percentage so we display both to fulfill all the needs of our users.
  • Sensor: Name you have given the sensor to identify it.
  • Sensor ID: If multiple sensors are exported you can distinguish which reading was from which using this number even if the names for some reason are the same.
  • Sensor State: Binary field represented as an integer containing information about the state of the sensor when the message was transmitted. (See “Sensor  State”)
  • Signal Strength: Strength of communication signal between the sensor and the gateway, shown as percentage value.
  • Text: Data transformed and presented as it is shown in the monitoring portal.
  • Voltage: Actual voltage measured at the sensor battery used to calculate battery percentage, similar to Received Signal you can use one or the other or both if they help you.

DMZ (Demilitarized Zone): DMZ or demilitarized zone is a physical or logical buffer between an organization’s Local Area Network and an external network, usually the Internet.

EULA (End User License Agreement): In terms of proprietary software, a EULA is the contract between the purchaser and the licensor, outlining the terms and conditions of proper use.


Heartbeat: The heartbeat is the amount of time between transmissions.

  • Sensor:  Check-in, how frequently the sensors checks in with the gateway.
  • Gateway:  Check-in, how often the gateway normally communicates with the servers.
  • Aware State:   How often the sensor transmits to the gateway while in the aware state.

Icons and Definitions:


LAN (Local Area Network): A computer network which connects computers within a limited area such as a home, school or business.

Link Mode: The time when the sensor is trying to connect to a gateway. The sensor sends a message on the first channel saying “I’m number 12345, can I talk to you?” If it doesn’t hear anything back it assumes there is not a gateway on that channel and tries the next channel. If it scans through all of the channels and receives no response, it will stop trying for two hours at which point the process will begin again. The scanning process only takes about 30 seconds but can take a day’s worth of the battery life.

Modbus: a serial communication protocol used for transmitting information over serial lines between electronic devices.

Monitoring Software:

  • iMonnit Basic: Online (Cloud ) based  single user application software to monitor sensor and gateway activity, receive notifications and manage the sensor network.

  • iMonnit Express:Application software to monitor sensor and gateway activity, receive notifications and manage the sensor network. Installed locally on PC (Can be stand-alone PC with no internet connection.

  • iMonnit Premiere: Online (Cloud) based Monitoring solution to monitor sensor and gateway activity, receive notifications and manage the sensor network.

  • iMonnit Enterprise:  Available for large organizations with specific data usage requirements. It provides the same feature set as iMonnit Online but has additional functionality to allow the organization to host and maintain its own sensor data.

NIST (National Institute of Standards and Technology): An agency of the U.S. Department of Commerce which is responsible for developing information security standards and guidelines, including minimum requirements for federal information systems. NIST certification is important because it supports and develops measurement standards for a particular service or product.

Notification (Alert): Email, text or phone message indicating a sensor has crossed a user-set threshold or an event has occurred. 

  • Inactivity:  Notification when your sensors have stopped communication with the servers. The default time period is 3 times the set heartbeat.
  • Low Battery:  Sends when a user-defined battery power percentage is reached, warning them to replace batteries.
  • Application: Notification which is sensor specific. The type of sensor will determine the options available.
  • Advanced:  Notifications with more capability, such as comparing past data points with current ones to determine if an alert needs to be sent.

OEM (Original Equipment Manufacturer): A term used when one company makes a part or subsystem which is used in another company's end product.

Polling:  For a gateway, refers to it checking to see if there is an urgent down message to be delivered. It is only used in conjunction with control sensors.

RMA (Return Merchandise Authorization):  Instructions for the return of a product or device for any reason.

RTD (Resistance Temperature Detector):  Measures temperature by correlating the resistance of the RTD element with temperature. These elements are used in our high accuracy sensors.

SCADA (Supervisory Control and Data Acquisition): A system operating with coded signals over communication channels to provide control or remote equipment.

Sensor State: The integer presented here is generated from a single byte of stored data.  A byte consists of 8 bits of data that we read as Boolean (True (1)/False (0)) fields.

       Sensor State

Sensors: - 2 types:

  • Event Type:  Sensors that respond immediately to an event as it occurs (think of event type sensors as yes/no data, Boolean).
  •  Reading Type:  Sensors that work on a timed basis to wake up at set intervals, gather data, transmit the data, then go back to sleep until the next interval.
Each sensor type can be in one or more of these forms:
  • Commercial Coin Cell: CoinCell battery powered (CR2032), 1.775 in x 1.04 in x 0.785 in
  • Commercial: AA battery powered (x2), 3.02in x 2.1 in x 1.27 in
  • Wi-Fi:  AA battery powered (x2), 3.02 in x 2.1 in x 1.27 in
  • Industrial: AA battery powered (3 VDC x 1) 3.7 in x 2.32 in x 1.38 in
  • Solar: Powered by arechargeable AA Lithium Iron Phosphate battery, 3.7 in x 2.32 in x 1.38 in

WAN (Wide Area Network): A network using such devices as telephone lines, satellite dishes or radio waves to span a larger geographic are than can be covered by a LAN

WIT: Smart sensor (Now called Commercial Coin Cell sensor).

WIT2: Smart Sensor (Now called Commercial AA sensor).