ATD Automatic Timer Disconnect
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BLUE SEA SYSTEMSATD Automatic Timer Disconnect


In stock online.
Model # 17949918 | Mfg # 7615UPC # 632085076153


ATD Automatic Timer Disconnect

Name Value
Amperage 120 Amps Continuous
210 Amps Intermittent (5 Minutes)
Multi Bank Chargers 2 Banks
Type Battery Isolator/ Combiner
Voltage 12 Volts DC

Product Overview

Adjustable time or voltage based Automatic Timer Disconnect (ATD) automatically shuts off devices to preserve battery power.

The 12V signal triggers relay to connect battery power to devices. When signal is removed the timer is activated and will disconnect devices after a preset time. Disconnect can be triggered based on time, low voltage, or removal of 12V signal. Low voltage will disconnect if time hasn’t been reached to preserve battery power.

Can be configured to be used as one of the following battery saving products:

Timer Disconnect

  • 12V signal triggers relay to connect battery power to devices
  • When signal is removed the timer is activated and will disconnect devices after a preset time
  • Timer ranges from 15 minutes to 4 hours
  • Optional charge sense can be used instead of 12V signal to reduce wiring
  • Test mode disconnects devices after five seconds to confirm that both the relay and timer are operational

Low Voltage Disconnect

  • Senses low battery voltage and automatically disconnects devices to safe power
  • Adjustable voltage setting at 11.0V, 11.5V or 12.0V
  • Low voltage setting can be used in conjunction with Timer Disconnect
  • Low voltage will disconnect devices prior to preset time to preserve battery power

Automatic Charging Relay

  • Automatically combines two batteries when charging off a single charging source (e.g. the alternator)
  • Isolates batteries when charging source is not present or discharging
  • Single side sensing design only monitors the voltage of the start battery
  • Ideal for auxiliary batteries that are AGM or significantly larger than the start battery


  • 12V signal will connect or disconnect relay without any time delay

Key Features

  • Time and voltage options can be turned off to allow 12V signal based disconnect
  • The clip-on cover insulates terminal connections
  • One-piece stainless flange nuts ensure safe and secure connections
  • Integrated LED indicates status
  • Rated IP66 and ignition protected
  • Nominal Voltage 12V DC
  • Input Voltage Range 9.5–16V
  • Continuous Rating 120A
  • Intermittent Rating: 5 min. 210A
  • (Combine) Amperage Operating Current 175mA
  • (Open) Amperage Operating Current 4mA
  • Cable Size to Meet Current Ratings 1 AWG (50mm²)
  • Maximum Cable Size 1/0 AWG (50mm²)
  • Terminal Stud Size 3/8"-16 (M10)
  • Terminal Stud Torque 140 in-lb (15.82 Nm)
  • Time Range 15 Minutes – 4 Hours
  • Charge Sense ON: Connected (3 sec) 13.0V or greater
  • Timing (10 sec) 12.75V or lower
  • Low Voltage Disconnected (10 sec) Battery Voltage < Disconnect Voltage
  • Over Voltage Disconnected (5 sec) 16.0V or greater
 WARNING: Cancer and Reproductive Harm -


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