CHESTER Input

This chapter describes the core functionality, hardware description, default configuration, and example JSON messages in the catalog application CHESTER Input.

caution

Some of the basics are not provided, as they are common for all CHESTER catalog applications. For example, see the chapter Platform Management on how to work with the interactive console.

Application Overview

CHESTER Input can be used to measure and send values of various analog and digital signals. Measured values can be preprocessed, buffered, and send in a bigger aggregated packet to save power in battery-operated variants.

CHESTER Input has these four inputs:

Type	Terminal	Input type	Input range	Example usage
Trigger	CH1	Digital NPN/PNP	0 - 28 V	Switch, button, relay, etc.
Counter	CH2	Digital NPN/PNP	0 - 28 V	Electricity S0 output counter
Voltage	CH3	Analog voltage	0 - 28 V	Various analog sensors
Current	CH4	Analog current	0 - 20 mA	Various current loop sensors

All these inputs and their options are explained in more detail in a chapter Input parameters and behavior,

Hardware Description

The catalog CHESTER Current hardware consists of the following ordering codes:

CHESTER-M-CGLS
CHESTER-X0B:A
CHESTER-Z

Optionally:

CHESTER-S2 with external temperature and hygrometer

Input parameters and behavior

For signal connection to CHESTER Input please follow terminal block pinout. Chester X0 is placed in a left slot A so you have to use terminals A1 - A8.

Trigger

This input can be connected to the button, switch, relay, etc. The behavior of the input is configurable.

When the input changes, the current timestamp is saved, and this information is buffered to send in the next report.
Optionally a change of input to an active or inactive state can be reported immediately or with a configurable delay to capture more input changes.
NPN/PNP input could be configured.
Minimal signal duration could be configured separately for active and inactive states.
Maximal number of reports per hour could be configured for data saving and better power consumption when powered by a battery.

Counter

This input counts a number of pulses.

Counter value is aggregated in configured period by counter-interval-aggregate and then reported in a batch by period set by interval-report.
NPN/PNP input could be configured (counter-input-type).
Minimal signal duration could be configured separately for active and inactive states.
Maximal number of reports per hour could be configured for data saving and better power consumption when powered by a battery.

Voltage

This input measures the voltage 0 - 28 V.

Samples are sampled with a configurable period. (analog-interval-sample)
Samples are then aggregated in the configurable interval. Minimum, maximum, average, and median are computed from buffered samples. (analog-interval-aggregate)
Each aggregated values have its timestamps and are sent in a batch in a report interval period. (interval-report)

Current

This input measures the current loop 0 - 20 mA. Configuration shares the same parameters with voltage measurement in the previous chapter Voltage.

External hygrometer (optional)

Optional external temperature and humidity sensor.

Samples are sampled with a configurable period. (hygro-interval-sample)
Samples are then aggregated in the configurable interval. Minimum, maximum, average, and median are computed from buffered samples. (hygro-interval-aggregate)
Each aggregated values have its timestamps and are sent in a batch in a report interval period. (interval-report)

Default Configuration

This is the default configuration (printed using the app config show command):

app config analog-interval-sample 60
app config analog-interval-aggregate 300
app config interval-report 1800
app config trigger-input-type npn
app config trigger-active-duration 100
app config trigger-inactive-duration 100
app config trigger-cooldown-time 10
app config trigger-report-active false
app config trigger-report-inactive false
app config trigger-report-rate 10
app config trigger-report-delay 5
app config counter-interval-aggregate 300
app config counter-input-type npn
app config counter-active-duration 2
app config counter-inactive-duration 2
app config counter-cooldown-time 10
app config hygro-interval-sample 60
app config hygro-interval-aggregate 300

Specific Commands

info

You can easily explore the whole command tree structure - start with the help command.

Command to set report interval in seconds:

app config interval-report <value>

Commands to set sample and aggregate interval for analog measurements (voltage measurement and current loop) in seconds:

app config analog-interval-sample <value>
app config analog-interval-aggregate <value>

Commands to set the input type for trigger and counter inputs. Valid values are npn or pnp:

app config trigger-input-type <npn/pnp>
app config counter-input-type <npn/pnp>

Commands to configure that trigger input will immediately report when changed to active or inactive level:

app config trigger-report-active <true/false>
app config trigger-report-inactive <true/false>

Command to limit the number of asynchronous reports in a one-hour window. This is used to save power in the battery-operated device or save the data plan. Standard periodic reports set by interval-report are not counted to this limit:

app config trigger-report-rate <value>

Command to configure a small delay between trigger event and reporting. This may be useful in the case where you want to wait a few seconds before reporting to sample another change of the trigger input. This parameter sets the time in seconds:

app config trigger-report-delay <value>

Commands to set the active and inactive time duration for trigger and counter digital inputs in milliseconds:

app config trigger-active-duration <value>
app config trigger-inactive-duration <value>
app config trigger-cooldown-time <value>

app config counter-active-duration <value>
app config counter-inactive-duration <value>
app config counter-cooldown-time <value>

Commands to set sample and aggregate interval for optional hygrometer (CHESTER-S2) in seconds:

app config hygro-interval-sample <value>
app config hygro-interval-aggregate <value>

Example JSON Message

{
  "frame": {
    "protocol": 1,
    "sequence": 95,
    "timestamp": 1668769692
  },
  "attribute": {
    "vendor_name": "HARDWARIO",
    "product_name": "CHESTER-M",
    "hw_variant": "CDGLS",
    "hw_revision": "R3.2",
    "fw_version": "(unset)",
    "serial_number": "2159018247"
  },
  "state": {
    "uptime": 172497
  },
  "battery": {
    "voltage_rest": 3.95,
    "voltage_load": 3.84,
    "current_load": 38
  },
  "network": {
    "imei": 351358815178303,
    "imsi": 901288003957939,
    "parameter": {
      "eest": 7,
      "ecl": 0,
      "rsrp": -90,
      "rsrq": -8,
      "snr": 8,
      "plmn": 23003,
      "cid": 939040,
      "band": 20,
      "earfcn": 6447
    }
  },
  "thermometer": {
    "temperature": 22.93
  },
  "accelerometer": {
    "accel_x": 0.07,
    "accel_y": 0,
    "accel_z": 9.8,
    "orientation": 2
  },
  "event": {
    "trigger_active": false,
    "trigger_inactive": false,
    "line_present": false,
    "line_not_present": false
  },
  "trigger": {
    "value": true,
    "measurements": [
      {
        "timestamp": 1668768211,
        "is_active": false
      },
      {
        "timestamp": 1668768215,
        "is_active": true
      },
      {
        "timestamp": 1668768217,
        "is_active": false
      },
      {
        "timestamp": 1668768220,
        "is_active": true
      }
    ]
  },
  "counter": {
    "value": 137,
    "measurements": [
      {
        "timestamp": 1668768211,
        "value": 12
      },
      {
        "timestamp": 1668768511,
        "value": 50
      },
      {
        "timestamp": 1668768811,
        "value": 73
      },
      {
        "timestamp": 1668769111,
        "value": 132
      },
      {
        "timestamp": 1668769411,
        "value": 135
      }
    ]
  },
  "voltage": {
    "measurements": [
      {
        "timestamp": 1668768211,
        "min": 9.75,
        "max": 9.85,
        "avg": 9.82,
        "mdn": 9.84
      },
      {
        "timestamp": 1668768511,
        "min": 9.83,
        "max": 9.84,
        "avg": 9.83,
        "mdn": 9.83
      },
      {
        "timestamp": 1668768811,
        "min": 9.83,
        "max": 9.84,
        "avg": 9.83,
        "mdn": 9.83
      },
      {
        "timestamp": 1668769111,
        "min": 9.76,
        "max": 9.84,
        "avg": 9.81,
        "mdn": 9.82
      },
      {
        "timestamp": 1668769411,
        "min": 9.75,
        "max": 9.85,
        "avg": 9.82,
        "mdn": 9.84
      }
    ]
  },
  "current": {
    "measurements": [
      {
        "timestamp": 1668768211,
        "min": 0,
        "max": 20.89,
        "avg": 6.42,
        "mdn": 8.17
      },
      {
        "timestamp": 1668768511,
        "min": 8.11,
        "max": 8.57,
        "avg": 8.44,
        "mdn": 8.52
      },
      {
        "timestamp": 1668768811,
        "min": 8.43,
        "max": 8.57,
        "avg": 8.49,
        "mdn": 8.48
      },
      {
        "timestamp": 1668769111,
        "min": 8.11,
        "max": 8.48,
        "avg": 8.38,
        "mdn": 8.43
      },
      {
        "timestamp": 1668769411,
        "min": 8.11,
        "max": 8.57,
        "avg": 8.44,
        "mdn": 8.52
      }
    ]
  },
  "hygrometer": {
    "temperature": {
      "measurements": [
        {
          "timestamp": 1668768211,
          "min": 22.03,
          "max": 22.28,
          "avg": 22.14,
          "mdn": 22.1
        },
        {
          "timestamp": 1668768511,
          "min": 22.38,
          "max": 22.5,
          "avg": 22.43,
          "mdn": 22.41
        },
        {
          "timestamp": 1668768811,
          "min": 22.61,
          "max": 22.75,
          "avg": 22.68,
          "mdn": 22.68
        },
        {
          "timestamp": 1668769111,
          "min": 22.78,
          "max": 22.86,
          "avg": 22.82,
          "mdn": 22.82
        },
        {
          "timestamp": 1668769411,
          "min": 22.55,
          "max": 22.74,
          "avg": 22.64,
          "mdn": 22.65
        }
      ]
    },
    "humidity": {
      "measurements": [
        {
          "timestamp": 1668768211,
          "min": 58.82,
          "max": 60.23,
          "avg": 59.73,
          "mdn": 59.99
        },
        {
          "timestamp": 1668768511,
          "min": 58.79,
          "max": 59.41,
          "avg": 59.26,
          "mdn": 59.36
        },
        {
          "timestamp": 1668768811,
          "min": 57.93,
          "max": 58.61,
          "avg": 58.23,
          "mdn": 58.09
        },
        {
          "timestamp": 1668769111,
          "min": 56.91,
          "max": 57.95,
          "avg": 57.53,
          "mdn": 57.63
        },
        {
          "timestamp": 1668769411,
          "min": 56.86,
          "max": 59.33,
          "avg": 57.85,
          "mdn": 57.83
        }
      ]
    }
  },
  "backup": {
    "line_present": true,
    "line_voltage": 12.7,
    "batt_voltage": 3.38
  }
}

CHESTER Input

Application Overview​

Hardware Description​

Input parameters and behavior​

Trigger​

Counter​

Voltage​

Current​

External hygrometer (optional)​

Default Configuration​

Specific Commands​

Example JSON Message​