12 volt Timer relay. Configurable time & delay on or off.
This timer operates after a single impulse in the same way as a timer relay but with the option of an ON delay or an OFF delay. The ON or OFF delay can be configured between 0.5 seconds and 6 hours.
The timer operates from 12 volts and has change-over contacts rated at 10 amps. This unit is ideal to provide a 5 minute front screen timer but must be used to switch a larger relay(s) to control the heater current. The timer relay will be destroyed if the unit is used to switch the heater current directly. If your heated front screen has separate connections for left and right, consider using two 40 amp relays with coil resistors and individual supply fuses to suit.
To provide a single trigger pulse, connect a momentary switch to timer terminal 87a and terminal 15. Connect terminal 30 to an ignition supply and 31 to earth. Terminal 87 is the positive timed output, connected to the power relay(s) coil(s). The power relay(s) positive supply should be connected to a battery feed and not an ignition feed.
When used as an ON delay, the timer relay turns on after the preset time delay when an ON/OFF switch is connected between terminal 30 and terminal 15. This is useful for delaying a second action after turning on a switch. At the point of switch off, the timer resets, ready for the next operation.
The Option Table:
0 = 0.5 ... 10 sec delay off        5 = 0.5 ...... 6 hrs delay on
1 = 5 ...... 60 sec delay off        6 = 5 ...... 60 min delay on
2 = 0.5 ... 10 min delay off         7 = 0.5 ... 10 min delay on
3 = 5 ...... 60 min delay off         8 = 5 ...... 60 sec delay on
4 = 0.5 ...... 6 hrs delay off        9 = 0.5 ... 10 sec delay on
Terminal 30 ---- Positive supply
Terminal 15 ---- Positive trigger input
Terminal 31 ---- Earth
Terminal 87 ---- NO relay contact
Terminal 87a -- NC relay contact