JBJ A.T.O. - Automatic Top Off System Water Level Controller Information


Q: How large of a pump can I plug into the A.T.O.?
A: The A.T.O. receptacle will handle pumps up to 2amp capacity.

Q: Can the Audible Alert be turned off?
A: Yes, it can be turned off if the "Speaker Buzzer" is removed from the circuit board.

Q: Why does my A.T.O. automatically shut off after a few minutes of operation even though the water level has not reached the float sensor?
A: All A.T.O. Controllers have a factory "Float Fail-Safe" duration time period of 3 minutes and 45 seconds of operation before power to the pump is turned off. The Pump LED will glow but power to the pump will not be turned on. This feature was designed to act as a safety mechanism in the unlikely event the float sensor(s) failed or if something was to get stuck in between the sensor(s). You will have to reset the float sensor(s) to restart the controller.

Q: Can I adjust the "Float Fail-Safe" duration time period?
A: Yes, the duration time can be extended to 14 minutes of operation. (Please see instructions below on adjustment.)
Reef Aquarium
How to Adjust the "Float Fail-Safe" Time Duration

Unscrew back panel off of controller (4) total screws Adjusting Dial is located towards the top in "Blue Color"
JBJ A.T.O. Adjust Float Fail-Safe Time Duration Step 1a JBJ A.T.O. Adjust Float Fail-Safe Time Duration Step 1b
Reef Aquarium
Step 2
Use a Phillips screwdriver and turn the dial COUNTER CLOCKWISE until it locks. This setting will give a operation mode time of approximately 14 minutes or until correct water level is reached.
Reef Aquarium
JBJ A.T.O. Adjust Float Fail-Safe Time Duration Step 2