This was meant to be an early warning for low battery.
To protect the rear two low batteries were placed for ditch defence.
In 1693 a lower circular battery was set up to control access to the Charente River.
Everything in the green, except for two amber lights: a low battery and an air fan that was running slower than design nominal.
The constant risk of low batteries is a significant concern for gadget users, in particular when traveling.
He films it until the camera says "low battery" then the sea washes the words away and the camera turns off.
Your battery's low, I know, but it'll last long enough.
When the controller he found has a low battery, he gets new ones but drops one down the basement steps.
In 1879, two contracts were let for the construction of an upper and a lower battery.
About an hour later, guns of the lower battery opened fire.