TECHNICAL SHEET :

The Electronic Fail-Safe Time Delay Device is based on generation of 24 V output by dc-dc conversion after a precise delay after power is applied to the device. For the purpose of fail-safe generation of output, design of FST is based on 8-bit reliable flash microcontroller and a stable quartz crystal controlled time base using its internal timer is used to provide the control outputs to dc-dc converter stage and the feedback inputs to check the outputs at various stages. The FST is enclosed in a Q-Series Relay base/cover and input /output terminals are provided on Q-Series relay plug board suitable to fit in a relay-rack.

The electronics time-delay device should operate satisfactorily either from primary or secondary cells or unsmooth full wave rectifier supply from single phase, 50 HZ sinusoidal AC Supply. The rated current, voltage and ambient temperature should be as follows : -

• Input Voltage : 24 V DC + 20%, - 10%
• Output Voltage : 24 V DC + 20%, -10%
• Output Current : 150 mA (Max)
• Operating Temperature Range : -10°C to 55°C
• Fixed Time Delay : 10/20/30/60/120 seconds