Sewer Monitoring

Application Notes

Application Background                                                                                                                                                                                      Printer Friendly Version

Water and waste utilities need to monitor sewer levels and flows. If there are equipment breakdowns within the sewer system overflows may occur. There are large fines and other penalties levied on water and waste utilities when there is a sewer overflow and the cost of cleanups is substantial.

application note sewer monitoring 1

Application Detail

Sewer overflow conditions can be detected with simple level limit switches which may be installed within the sewer pipe at different levels, to trip a level limit alarm. Sewer flows can also be measured with the Unidata Starflow ultrasonic Doppler flow meter installed on the bottom of the sewer pipe.

Unidata-Industrial Outflow Monitoring Starflow

The overflow monitoring application is relatively simple. There could be a set of mechanical limit switches installed inside the sewer pipe, perhaps 3 switches at low medium and high positions within the pipe, usually mounted on an angle bracket which is then inserted into the sewer pipe.

float limit switches

Each limit switch is wired back to the Neon Metering Module which is set up to detect when the limit level is exceeded. The Neon Metering Module alarm is activated and this alarm condition is sent to the Neon server via cellphone, satellite networks or local WI FI networks. The Neon Server processes the alarm and sends emails and / or text messages to alert operators of that out of limit and potential overflow condition.

Water and Waste utilities often need more sophisticated alarm handling, with multiple levels of escalation, such that if the first alarm was not acknowledged and attended to by the first person, within a pre-determined time, further alarms are be sent to different escalation contacts, to make sure the potential overflow condition was being attended to.
The cellphone based Neon Metering Modules are powered by a single lithium battery, and can operate for more than two years on that one lithium battery, so they are simple to install without the need for any power infrastructure. The Satellite and WI FI models require a small sealed gel battery and a very small solar panel.Some typical limit switches are shown, along with the simple wiring, and the battery arrangement.
A Neon Metering Module (NMM) can be wired up to a Unidata Starflow ultrasonic Doppler flow meter to measure the velocity and the depth, and then calculate the flow reading based on the size and the shape of the pipe, which can be rectangular, circular or ovoid.

application note sewer monitoring 5

There may be a need to record routine levels and flows over a period, say over 24 hours, and then and then upload that routine data once per day at a predetermined time, e.g. at midnight.
You should decide on an appropriate sensor reading interval, typically this would be to read the sensors every minute, and store the sensor data in memory every 5 minutes and send the sensor data to the Neon Server every few hours.

ip datalogger neon remote module

To conserve battery life, equipment is set to sleep between sensor readings, however limit switch changes are detected immediately even when the equipment is asleep. These limit switch changes trigger an immediate alarm transmission to the Neon Server and a text message can be sent to the relevant personnel to alert them of this alarm condition.

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Another consideration is how to power the Neon Metering Module. A power budget should be performed by Unidata engineers to decide the best power method, either solar panels and sealed lead acid batteries or lithium batteries
In regard to mounting, the starflow instrument should be mounted inside the pipe using a pipe band or a mounting bracket. Care should be taken to make sure the installation is mechanically smooth, so any debris in the sewer flow is not caught on any sharp edges of the instrument, the mounting plate or the cable.

water monitoring starflow expanding band 6705D
water monitoring starflow expanding clamps 6705A and 6705B

Typical Configuration

Options for Application Specific Instruments / InputsUnidata Part NumberDescription
Ultrasonic Doppler Instrument - Velocity, Depth & Flow6526J-21Starflow Ultrasonic Doppler Instrument 0-2m
Ultrasonic Doppler Instrument - Velocity, Depth & Flow6526J-51Starflow Ultrasonic Doppler Instrument 0-5m
Ultrasonic Doppler SDI-12 Instrument - Velocity & Depth6527AStarflow QSD
Water Level Instrument6541C-11WLI with 500mm Pulley & Alk Batt Metric (Imperial version available)
Float6541F-115WLI Float - Cylinder 115mm (other options available)
Float Line6541D-MWLI Beaded Floatline Metric (Imperial version available)
Options for Neon Telemetry - NRL / NRT / RTU / Field UnitsUnidata Part NumberDescription
Neon Remote Logger 16 Channels3016AOptions Available: 3G/4G Cellular, Ethernet, Globalstar, Inmarsat, Iridium SBD and LoRa
Neon Remote Logger 8 Channels3008AOptions Available: 3G/4G Cellular, Ethernet, Globalstar, Inmarsat, Iridium SBD and LoRa
Neon Remote Logger 4 Channels3004AOptions Available: 3G/4G Cellular
Neon Remote Logger 4 Channels M Series3004A-MOptions Available: 3G/4G Cellular, Ethernet, Microsatellite, Iridium SBD and LoRa
Cellular RTU 3G/4G2013F-AB03 / 2013F-AB04Neon Metering Module 3G/4G with Antenna and Li Battery
Cellular RTU 3G/4G - Industrial2016F-AB03 / 2016F-AB04Neon Remote Terminal 3G/4G with Antenna and Li Battery
Low Earth Orbit Satellite Globalstar2015F-AB0NRT Satellite Globalstar Modem with Antenna and three Li Batteries
Ethernet2017F-0B0-1 or 3NRT Ethernet with single or triple Ethernet Ports with three Li Batteries
Equatorial Orbit Satellite - Inmarsat2018F-AB0-1 or 3NRT Ethernet with single or triple Ethernet Ports with three Li Batteries
LCD Display2500ENRT LCD Display
NRT Field Termination Strip2103F2015F,2016F,2017F, and 2018F NRT FTS
NRT Firmware Option2303A-8M8M Extended Memory Option
NRT Firmware Option2303A-8M-CAM8M Extended Memory & Serial Camera Option
NRT Firmware Option2303A-CAMSerial Camera Option
Options for Neon Application Software - Customer ServerUnidata Part NumberDescription
Neon Application Software2302ANeon Server Software Licence Incl 5 NAL
Neon Application Software2302A-10Additional 10 NRT Access Licences
Neon Application Software2302A-20Additional 20 NRT Access Licences
Neon Application Software2302A-50Additional 50 NRT Access Licences
Options for Neon Application Software - Unidata ServerUnidata Part NumberDescription
Neon Application Software2301ANeon Data Initial Subscription Setup Fee
Neon Hosting Service2301A-01Neon Data Service Fee for 1-50 NRTs
Neon Hosting Service2301A-02Neon Data Service Fee for 51-100 NRTs
Neon Hosting Service2301A-10Neon Data Service Fee Metering
Options for Conventional Dataloggers / Field UnitsUnidata Part NumberDescription
Neon Remote Logger 16 Analog Channels / Touch Screen Display3016A-00016 Ch NRL (Superseded Prologger 7001D)
Neon Remote Logger 8 Analog Channels / Touch Screen Display3008A-0008 Ch NRL (Superseded Stalogger 6004D)
Neon Remote Logger 4 Analog Channels / Touch Screen Display3004A-0004 Ch NRL (Superseded Micrologger 8010C)
Starlog V4 Management Software6308A-AUEStarlog V4 Full Licence Key