Transformer Dry-out System Amperis DryMAX®

Dehydrate wet transformers without taking them out of service!

The Amperis DryMAX® transformer dry-out system incorporates all the necessary features to allow a transformer to remain in-service while moisture from its insulation is effectively removed. The system is safe with several alarm features that shut the system off, isolating it from the transformer, in the event of any abnormal signal. The Amperis DryMAX®5-1 unit provides a non-intrusive, cost effective and convenient method of maintaining transformers in a dry condition. In addition, once the transformer is dried, the system can be retrofitted with Activated Alumina cartridges to reduce acidity in the transformer oil. This flexibility allows increased oil processing application compared to heat and vacuum systems.

APPLICATIONS

• Dry wet transformers and insulation
• Dry transformers not braced for vacuum
• Dry transformers that cannot be taken out of service

BENEFITS

• Transformer remains in-service during process
• Reduce transformer dry-out costs
• Improve oil dielectric values
• Improve transformer power factor
• Operates continuously unattended
• Extend oil service life
• Extend transformer service life

SYSTEM OVERVIEW

The Amperis DryMAX® oil processing system is designed to allow a transformer under load to dry itself out. A quantity of four part number SD-1107 Superdri® cartridges are installed in the filter vessel, through which oil is processed at a rate of 19 l/min. The filtering system removes dissolved water from oil to less than 10 ppm, and includes 1 micron nominal particle removal capabilities. The process does not affect dissolved gas in oil, and does not remove oil oxidation inhibitors. The system is complete with all components necessary to monitor the mechanical and electrical operating conditions of the unit. The system includes components to purge air during start up and after filter changes.

PROCESS OVERVIEW

The on-line dryout process is designed for safe, unattended, 24-hour operation. The system suction line is connected to the transformer bottom fill connection. The oil is then returned from the Amperis DryMAX® to a top connection valve. The number of cartridge changeouts required to dry the transformer insulation to an acceptable level and cartridge change-out intervals will vary according to moisture content and moisture transfer rate from the insulation to the oil. One set of Superdri® cartridges will remove a minimum of 1.4 gallons of dissolved water from the oil.
Periodic moisture readings, from both the inlet to and outlet from the system can be taken to determine the amount of moisture being removed and are also used to determine when cartridges should be changed.

GENERAL CONDITIONS AND GUIDELINES

The Amperis DryMAX®5-1 relies on load from the energized transformer to push moisture from the insulation out to the surrounding oil. As the moisture is released into the oil, it is removed by the Superdri® cartridges which continually dry the oil to less than 10 ppm total water. Transformer top oil temperature should be kept at least 40 - 60 degree C for moisture equili bration between insulation and oil to continue in a timely fashion. A single set of Superdri cartridges will remove approximately 5,3 liters of water. Cartridge performance can be monitored by observing the Doble DOMINO® moisture sensor (see options below). The process will not release moisture back into the oil even if cartridges are fully saturated.

Amperis DryMAX® DATA SHEET

MODEL	Amperis DryMAX®
	Amperis DryMAX® transformer dry-out system
SPECIFICATIONS
MAINS	230 V, 1 Ø, 50 Hz, 7,6 m  power cord inclusive.
CONTROL UNIT	Enclosure IP66. Motor starter, motor overload protection, PLC, start/stop/reset switch, run light indicator, high pressure cutoff switch and indicating light, and elapsed hour meter.
ELECTRIC MOTOR	½ hp (372,8 W), 1750 rpm, TEFC
FAN	6¨ (15,24 cm) for enclosure ventilation, with thermostat and filtered louver.
ELECTRONIC FLOW METER	0 to 113 liters per minute indicates flow rate, resettable batch totalizer, and cumulative gallons pumped, battery powered.
OIL PUMP	18,9 liters per minute, positive displacement gear pump with mechanical seal and internal pressure bypass.
VACUUM PUMP	85 liters per min, close coupled motor and wired to main electrical control box for power source.
COAXIAL HOSES WITH OIL LEVEL ALARM	7,5 m length, coaxial lengths of suction and discharge 3/4” hose are provided with N.C. solenoids wired to main control panel. If a leak should develop on the hose connections to the transformer, oil will collect in the bottom of the enclosure and the system will shutoff automatically. Extra contacts are provided for remote alarm detection.
SELF DRAINING	Oil in the vessel is safely pumped back into the transformer during cartridge changeouts.
OIL LOW LEVEL RELAY	A dry contact relay is provided that can be wired to the transformer’s low oil level alarm to shut the system off if a low oil level is sensed.
DATACHABLE HOSES	Have disconnect fittings at the enclosure end. When disconnected, the hoses can be stored more conveniently in a separate hose storage area.
OPTIONS
Doble DOMINO® on-line direct reading moisture sensor continuously displays oil temperature and ppm of total water in the oil (or percent saturation of the oil). The piping layout of the Amperis DryMAX® system allows easy checking of both the influent and effluent moisture contents with a single sensor. A “Change Filter” alarm light is also mounted to the control panel door.
DIMENSIONS
Depth: 91,94 cm Width: 96,52 cm Height : 124,46 cm (216 cm with lid open) Shipping weight : 510 kg
ORDERING INFORMATION
Amperis DryMAX®5-1	Standard unit, 230 V CA, 50 Hz
746Y012	Optional moisture sensor, 230 V CA, 50 Hz
SD-1107	Superdri® cartridge, 4 required per change-out (not included with unit)
LB-1107	Activated alumina cartridge for acid removal, 4 required per changeout
WARRANTY
2 YEARS