Brown-Out Timers

Brown-Out Timers

A Few Words about 'Brown-Out Timers'


Brownout reset is mostly employed in microcontrollers like pic (BOR) which triggers an interrupt when the Vcc supply voltage falls lower that safe working voltage, due to momentary power supply fluctuations. The safe working voltage of micro is >4v this voltage is necessary to maintain the contents of RAM and proper execution of micro. If voltage drops below the safe level the RAM flip-flops loses their charge and their contents becomes junk and values in instruction pointer becomes corrupted and micro behaves abnormally. Hence most of micro manufactures include this kind of reset to safely prevent micro going crazy and when the voltage returns to normal level micro start executing from the reset address.

Brown-Out Timers


Application: Brownout Timer

Description:

The GBP Brownout timer is intended to reset apparatus which employ electromechanical control relays following a momentary partial or total supply interuption.

Our unit combines the function of an extremely fast under-voltage relay and a "Delay On" timer. The response of the unit is purposely tailored to follow the characteristics of the electromechanical device providing the best possible protection.

The range offers a large choice of options so you can select the best product for your application.
Choice includes:

- TIME RANGE - 9 adjustable options
- OUTPUT RELAY MODE - 3 options
- RESPONSE TIME - 3 options
- OPERATION VOLTAGE - 6 options
Trip Delay Timer
Where fitted the ‘Trip Delay Timer’ will inhibit the output contacts from releasing immediately a fault is detected.
The trip delay time is adjustable up to either 10 or 30 seconds depending on the model and will be either a ‘Standard’ delay or a ‘True’ delay type.
The 'Standard' delay type will require around 50% nominal supply voltage to be maintained for its operation, in the case of a total loss of power the unit
will trip with a minimal delay of approximately 0.5 seconds. This type of timer will allow the unit to ride through a short term voltage dip but not a total
power loss.
The 'True' delay timer is not dependent on the supply voltage for its operation. The timing function will be available in the case of either a partial or total
supply failure. This type of timer will allow the unit to ride through either a short term voltage dip or a total loss of power lasting up to 30 seconds.
Power On Delay Timer
Where fitted, the ‘Power On Delay Timer’ will delay the output contacts from energising immediately the supply voltage is applied to the unit for a period
of up to 30 seconds.
The supply voltage will have to satisfy the conditions set by the supply monitoring relay for a healthy supply continuously for the ‘Power On Delay’ timing
period before the output contacts will energise.
If the unit detects a fault and releases the output contacts the supply voltage will once again have to satisfy the requirements of a healthy supply continuously
for the ‘Power On Delay’ timing period before the output contacts will re-energise.