J-Tech Engineering - DC Uninterrupted Power Supply

DC Uninterrupted Power Supply

250Volts DC input variable frequency 3-phase output supply with 1350W UPS

The above image is of the first installed unit. This unit is designed to run in a DC-only environment. The operating input power is 250V DC. Power is quite dirty, subject to large spikes, and continuous surges & sags. AC power is not available in this environment.

The unit has the following feature set:

Microchip PIC16C71 microcontroller for monitoring all aspects of the system.
Twin Hawker Energy batteries providing 13 Ampere·Hours of current at 24 V DC.
Step-up hardware to take input power from 24 V DC up to approximately 288 V DC.
1350 Watts of power available in 30 second intervals in the event of a power failure.
Up to 10 successive failures can be handled safely with no recharge interval.
Step down hardware to take 250 V DC power down to 24 V for battery charging. Charging takes approximately 1.5 hours for a fully depleted battery.
Digital temperature sensor residing between the batteries to monitor temperature. This is necessary as the customer's operating environment has temperature variations from 20°C to 60°C. The charging voltage of lead-acid batteries is temperature dependent, and without careful charge-voltage control, battery life can be dramatically shortened.
A series of status indicators to the operator (remote location) providing information as to the state of the batteries and the charging system.
Large surge suppression network in front of all delicate circuitry. This unit can withstand surges in excess of 10 times the supply voltage. Normally surges are generated by relay contactors in the customer's environment opening up on inductive loads such as electromagnets and hoist motors.
Three-phase variable frequency power inverter for driving the customer's equipment.

This product is sold by Johnson Industries, Ltd. General inquiries regarding purchasing can be directed to:

Johnson Industries, Industrial Brake Division

Inquiries regarding designing and programming with microcontrollers and motor control in general can be directed to J-Tech Engineering. Please see the company info page for contact information.