A heartbeat is a simple broadcast packet sent at a predetermined interval.  The purpose of the packet is to announce to everyone that the device “is still alive.”

The Insteon RemoteLinc 2 is a battery powered insteon remote, that remains in a sleep state when it is not sending messages.  In this state the remote does not listen or respond to any packets sent to it.

As a battery operated device, the remotelinc will eventually need to be recharged, and it would be nice to know when a recharge is needed rather than finding out when the device doesn’t work.  The remotelinc has a command to query the battery level, but this query won’t work if the device is asleep.

This is where a heartbeat message would be nice.  It would automatically wake up the device at a periodic interval, allowing a battery level request to be sent to the device.

Best I can tell, the Remotelinc heartbeat function has been disabled or not included.  The following settings are supposed to control the hearbeat function:

Awake Interval	Sets the amount of time the Remotelinc remains awake with no activity.	This is editable
Sleep Interval	Sets the amount of time the Remotelinc remains asleep, before waking up to send a heartbeat message.	The device ACKs my changes, but the settings on the device don’t change.
Broadcast Number	Sets the number of heartbeat messages that should be sent every time the sleep interval expires.	The device ACKs my changes, but the settings on the device don’t change.
NoIAmAwake Bit	A single bit to disable sending heart beat messages, presumably overrides all of the other settings.	The device ACKs my changes, but the settings on the device don’t change.

Other users have reported similar problems over at the Indigo support forum.

As a work around, Misterhouse will send a battery level request immediately after receiving a message from the RemoteLinc.  The RemoteLinc will stay awake after sending a message for the amount of time specified in Awake Interval, I set mine to 10 seconds. Battery level requests will only be sent if the amount of time since the last battery level response has exceeded a defined threshold.

All of this works well, except for rarely used devices.  It is possible that such a remotelinc could die without there being a chance to query its battery level.