POWER RECTIFIER SPECIFICATIONS.pdf

SPECIFICATIONS FOR DYNAPOWER PRECISION ENGINEERED DC POWER SUPPLY

1.0 Rating: All units are rated at 100% continuous full load output, plus the following additional overload capabilities:

• 125% rated load current continuously for two (2) hours following continuous 24 hours operation at full output.

• 200% output for ten (10) seconds following 100% operation for 24 hours at full output.

2.0 Operating Conditions: Equipment is designed for operation in a 30°C average, 40°C maximum ambient and a maximum altitude of 3,300 feet. Please consult the factory if water cooled units are intended to be stored or operated near or below freezing temperatures, or if any equipment is expected to be subjected to temperatures below 5°C.

3.0 Heat Sinks: Diodes are mounted on cooling surfaces designed to remove heat from the devices while in operation. Air cooled designs employ finned aluminum extrusions to dissipate heat to the surrounding air.

Individual clamping structure is laid out for each device to maintain proper compression and allow for individual device maintenance. This conservative design results in substantially greater cooling than other methods which minimizes semiconductor junction temperatures.

4.0 Semi‐conductors: Diodes are selected to be operated at an extremely conservative utilization level of the device rating. This conservative design coupled with an oversized cooling system ensures low junction temperatures on the semiconductor devices and provides long term, reliable operation. Each thyristor is fitted by an R‐C network for protection.

5.0 Transformer: Dynapower transformers are conservatively designed to provide an efficient, transformer that offers the customer optimum performance. These transformers, which form the heart of any rectifier, are manufactured in the following manner:

Winding Material: Electrolytically pure copper.

Core Material: M6 grade, grain‐oriented silicon steel provides good flux transfer and low eddy current losses.

Insulation Material: Class 220°C insulation is employed within and between primary and secondary windings.

Encapsulation: The coils are vacuum pressure impregnated by varnish and then baked to cure.

Varnishing provides additional electro‐mechanical strength and protection from the operating environment.

Air Cooling: Air ducts are designed into winding to promote cooling air flow.

All coils are wound for stress distribution under fault conditions to provide superior mechanical strength.

6.0 Controls: Each rectifier includes the following controls located on the front panel of the main rectifier cabinet:

• 4 ½” Analog Ammeter, 2% F.S. Accuracy

• 4 ½” Analog Voltmeter, 2% F.S. Accuracy

• “Power‐on” pilot light indicator

7.0 Protection: All Dynapower rectifiers have a multi‐layered protection scheme, which includes:

• Diode over temperature sensors on each phase (3 total)

• Transformer over temperature sensors on each coil (3 total)

• Electric strip heaters with thermostat (separate power source required)

8.0 Transient Protection: A set of surge suppressers are provided to protect against voltage surges from both AC & DC sides as well as providing DVSS/DT protection.

9.0 Enclosure Construction: Air cooled rectifier cabinets are designed as NEMA 3R structures. The heavy duty industrial design includes a frame which is constructed from heavy‐duty formed steel welded together to form a strong foundation. All panels and screens are manufactured with high quality steel, and the entire assembly is then finished inside and outside by degreasing and acid resistant enamel paint. Standard construction has DC busbars terminated inside of the cabinet. This enclosure/chassis includes lifting eyes for use by a crane.

Additionally, Forklift holes will be at the bottom of the unit for lifting from the bottom.

10.0 Cooling: Dynapower’s attention to detail in the design and construction of the cooling systems ensure that heat generated during normal operation is removed from each component. This conservative design approach substantially increases the reliability providing our customers with rectifying systems that are virtually maintenance free.

Air cooled equipment use totally enclosed ball bearing motors to drive shrouded fan blades in an updraft configuration with an open, screened base and will vent out the side of the enclosure through louvered openings. A minimum of 2.5 feet clearance is required around the rectifier to allow for adequate cooling air flow and access.

On all designs, an internal sub‐panel separates electrical control components such as contactors, relays and electronics from the main rectifier section, and in the case of air‐cooled machines, from the cooling air stream.

11.0 Manuals: TWO (2) Sets of operating and installation instruction and print are included.