North American two-way gas SmartPoint modules
The following describes the alarms, errors, and warnings for the North American two-way gas water SmartPoint modules.
North American Two-Way (NA2W) SmartPoint modules monitor their operation for abnormal conditions, such as failure to read a meter, or exceptional conditions, such as water leak detection. When one of these alarm conditions is detected it is logged in non-volatile memory. If the endpoint is configured for fixed-base mode, a message is then transmitted to the RNI to notify it of the abnormal condition.
The primary means of communicating alarm conditions to the RNI is via the alarm message. The alarm message is used as a general status report as well. An alarm message will be transmitted once per week, subject to dithering, to indicate general endpoint status such as the battery voltage, temperature, and so on. This weekly alarm message is transmitted even in the absence of any detected alarm conditions.
| SmartPoint event name | Meter type | Event description | Event trigger |
|---|---|---|---|
| Broken Pipe | Direct and remote mount | Indicates the meter has detected an excessive flow rate of gas for a specified duration of time. To detect a broken pipe condition, the SmartPoint module monitors the rate at which the gas meter produces pulses. The SmartPoint module monitors the amount of time between consecutive pulses, and if the time is less than the configured threshold value the SmartPoint module initiates timed monitoring of the flow rate. If the excessive flow rate continues (time between pulses remains less than the threshold) for an amount of time longer than the configured broken pipe time, the broken pipe alarm is triggered. The broken pipe threshold, specified in time between pulses, is related to the actual flow rate through the meter based on a formula involving the meter index drive, resolution, and other variables. The broken pipe threshold is selected in real units at the time of installation using a handheld device. The handheld device uses the other meter configuration parameters to translate the actual flow rate into time between pulses. | Threshold time: Choose between 4-1020 milliseconds in 4 ms increments, or 1-255 seconds in second increments. Time duration: 0, 5, 10, 15, 30 or 60 seconds. |
| Cut Wire Tamper | Remote mount only | Indicates that the SmartPoint module has detected an attempt to tamper with the meter reading by severing the connection between a remote pulse meter and the SmartPoint module. | At the scheduled meter reading (MSR) time, the SmartPoint module checks the cut wire detection circuit; this circuit is a current loop to the remote meter. If the current loop is interrupted (the wire is cut), the alarm is triggered. |
| Low SmartPoint Battery Volts | All | Indicates that the SmartPoint module battery voltage is low. The battery voltage is sampled immediately before every transmission. | If the voltage is less than the threshold of 3.3V, the low battery alarm flag is set. |
| Magnetic Tamper | Direct mount only | Indicates that the SmartPoint module has detected an attempt to tamper with the meter by application of a magnet to prevent the reed switches from operating. For a direct mount meter, a third reed switch is used to detect attempted tampering by applying a magnet to the SmartPoint module. If the SmartPoint module detects the tamper switch is closed the magnetic tamper alarm is triggered. | To prevent false detection of the magnetic tamper, a debounce interval of two seconds is applied after initially detecting the tamper switch is closed. After the two second interval, if the switch remains closed the alarm condition is triggered. |
| Reverse Flow | Direct mount only | Indicates the SmartPoint module has detected gas flowing in the reverse direction through the meter. For a direct mount meter, the reed switch inputs are configured as a quadrature encoder. With the quadrature inputs, the SmartPoint module can determine the direction of rotation of the gas meter drive dog and thus the direction of the gas flow. When the SmartPoint module detects a reverse flow condition, it will accumulate the reverse pulse count. When the number of reverse pulses detected exceeds the programmed reverse flow threshold, the reverse flow alarm is triggered. | Configuration value: 1, 2, 5, 10, or 100 pulse counts. The threshold value can be set to 0 to in effect disable the alarm and the SmartPoint module does not monitor or report any reverse flow alarms. Drive rotation: Configure the forward flow direction of the drive dog rotation to clockwise or counter-clockwise rotation to detect forward versus reverse flow. |
| Tilt Tamper | Direct mount only | Indicates that the SmartPoint module has detected tampering by physically tilting the SmartPoint module (the module was removed from the gas meter). The SmartPoint module contains a tilt switch that closes if the module is tilted more than 45 degrees beyond vertical. | To prevent false detection of tilt tamper, a debounce interval of two seconds is applied after initially detecting the tilt switch is closed. After the two second interval, if the switch remains closed the alarm condition is triggered. |