HotDrop Power Modes
The HotDrops are normally powered by the circuits that they are monitoring. This is done by inductively harvesting the electromagnetic field created by the flow of alternating current. This has huge advantages as there are no batteries to maintain or replace and should last for many, many years.
When there is little or no electricity flowing through the circuit (eg. 0 to ~500 milli-amps), the HotDrops will not be receiving power and cannot measure or transmit data (they would be in a sleep or wait state until current begins flowing again). Depending on what the HotDrops are monitoring (i.e. HVAC or pumps), electricity can stop momentarily and then start again. To manage through these short outages (and continue powering the processors that monitor the power states) the HotDrop has capacitors that charge-up in voltage (to 5.0 VDC max) during harvest periods.
Vutility monitors the voltage on the HotDrop capacitors to manage transmission and sampling-rate adjustments, based on the remaining energy level on the HotDrops. The voltage/power level in the capacitors can indicate if projected current flows are adequate to maintain the transmission and sampling rates. If not, then the device can autonomously opt to enter one of three modes; Standard Mode, Low-Power-Mode or Measuring-Only-Mode (Table 1).
Vutility’s goal is to drive the most frequent transmissions of useful data possible by maximizing the power stored by capacitors combined with a power-saving-mode. The Low-Power-Mode conserves enough power to allow you to see your very-low-current readings even longer and at lower thresholds of current in a temporarily slowed but consistent delivery.