Associates an existing threshold alert with one or more ESA channels

Use this endpoint to attach an alert that was created without channels (or add more channels to one that already has some) to specific ESA channels. All channels must be active, accessible to the caller, and eligible for the alert. A channel already associated with this alert cannot be added again.

A channel is eligible only if it is a primary value or primary demand channel, has a summarization method the alert type and direction allow (Max or Average for ‘above’; Max, Average, or Min for ‘below’; Sum for ’total over time’), and has exactly the alert’s unit. Units must match exactly, not merely share a unit type: no unit conversion is performed anywhere, so a kWh channel cannot be used with an MWh alert. A meter whose channels carry different units therefore needs one alert per unit. For ’total over time’ the alert’s Interval must also be a whole multiple of the channel’s interval (it may equal it), since the total is accumulated from whole channel intervals. Use GET /esaalert/{alertId}/channels to list the channels that satisfy all of this.