Description of the Shut Down Timer (SDT)
The SDT protects the automobile battery from over discharge by shutting OFF up to 30 (20)amp
loads at a preset time after the engine is shut down or when the battery is discharged to a low volt-
age level. The SDT also protects radio or computer equipment from damage due to low or high input
voltage as experienced with alternator failure or improper voltage jump-starts.
An emergency switch allows 12 minutes of operation after the SDT shuts down the equipment.
An ignition switch input is provided as an optional activation method but is not necessary. The SDT
is normally activated by sensing the alternator charge voltage level applied to the battery. When the
alternator goes OFF the timed sequence is started.
A unique feature of the Lind SDT is that it allows full testing of the system after installation. Mo-
mentary closure of the test switch reduces the delay time by a factor of 100 to allow a quick test of
the system timing function.
Timer start
The timer contacts will close when the engine is started and the alternator is charging the battery
(battery voltage exceeds 13.5 (27) volts). SDT timing will start when the engine is turned OFF and
the battery voltage decreases to below 13 (26) volts.
Optional connection of the IGN terminal will result in the timer starting when the ignition switch
is opened. Note - If the IGN terminal is connected to the accessories position of the ignition switch,
the loads will be energized with the key in the accessories position.
*Special Note: If the vehicle electrical system does not exceed 13.5 VDC with the vehicle running,
the “IGN” terminal connection must be used or incorrect Shut Down Timer operation will occur.
Timer Setting
The SDT ON time after engine shut OFF is set with the potentiometer on the top of the SDT unit.
A small screwdriver or key can be used to set the potentiometer.
SHUT DOWN TIMER SPECIFICATIONS
Battery Voltage Sensing turn-on threshold:
>13.5(27) V
Battery Voltage Sensing timer start threshold:
<13.0(26) V
Ignition On threshold (if used):
>5(10)Volts
Ignition Off threshold(if used):
<2.5 (5)Volts
LED Flash Rate - Normal timing:
2 seconds
LED Flash Rate - Test Mode timing:
0.5 seconds
High Battery Voltage disconnect threshold:
>18(36)Volts
Low Battery Voltage disconnect threshold:
<10.5(21) V
Low Battery Voltage disconnect delay:
>10 seconds
Input voltage range:
9-18(18-36) V
Maximum load: (Two output connections):
30A{15A ea.} (20A{10A ea.}
Current draw in OFF mode:
9 mA
Current draw in ON/TIMING mode:
95 mA
Time Delay adjustment range:
(0 sec. - 4 hrs.)
(model dependent)
(5 sec.-2 hrs.)
(12 min.-18 hrs.)
Over-ride Mode time setting:
12 minutes
(over-rides time adj. setting)
Test Mode speed up rate:
x 100
Operating temperature
-50˚ to 75˚ C
Summary of Contents for DC Power Adapters
Page 132: ...MaxPower User s manual ...
