Descriptions

A transformer is an electrical device that is used in AC power distribution systems to safely “step up” or “step down” voltages to meet the incoming power requirements of connected equipment. Transformers achieve this goal without modifying the frequency or amount of electrical power to help ensure connected devices can operate reliably.

There are two primary types of transformers that are defined by the insulation used within the enclosure: dry-type and liquid-filled.

Unlike their liquid-filled counterparts, dry-type transformers do not incorporate oil, silicone or liquid to dissipate excess heat and meet temperature classification requirements. Instead, the coils within a dry-type transformer are constructed of a gaseous or dry insulation medium.

The dry type transformer is of two types. They are cast resin dry type transformer (CRT) and vacuum pressure impregnated transformer (VPI). On this page, we will explore the basics of Lingfran VPI low voltage dry type transformers and their most common configurations.

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Specifications

Type		Isolation Transformer
Rated Power		35KVA
Input	Voltage	220V
	Tap	None
	Connection	Delta or Wye
	Frequency	50Hz±5% or 60Hz±5%
	Phase Number	Three
Output	Voltage	380V
	Tap	None
	Connection	Delta or Wye
	Frequency	50Hz±5% or 60Hz±5%
	Phase Number	Three
Vector Group		Dyn11, Yyn0, etc
Impedance Voltage		4%
Efficiency		≥98%
Duty Cycle		100% Continuous
Winding Conductor Material		Copper
No Load Current		<4%
Display		Analog Voltmeter
Insulation Class		F
Insulation Resistance		≥10MΩ
Withstand Voltage		2500V , 1 Minute, No Flashover and Damage
Coil Temperature Rise		≤120K
Cooling Method		Natural Ventilation (AN)
Working Environment		Ambient Temperature: -10℃ to +45℃
		Relative Humidity: ≤95% (non-condensing)
		Altitude: ≤1000m
Protection Degree		Indoor IP20 (NEMA 1)
Standards		In Accordance with IEC and EN

Remarks:

1. Specifications may subject to change without prior notice.

2. Specifications with multiple configurations, please advise your specific requirements for accurate price.

3. Three requirements that cannot be met by transformer.

    3.1 Increase or decrease the incoming or load power.

    3.2 Change frequency.

    3.3 Convert single phase to 3 phase.

4. Please use our  to change the frequency or transform single phase to 3 phase.

5. Custom-made service is available, please advise your specific requirements if you do not find the suitable specifications from above form.

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Detailed Images

 

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220v to 380v or 380v to 220v, we can manufacture both step up or down transformers.

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Buying Guid

The important design parameters for a dry type transformer are given below. Please provide as many parameters as yo can.

1. Primary voltage.

2. Secondary voltage.

3. Number of phases.

4. Power rating or capacity (kVA).

Tips: To do this you must determine the largest load you can expect at any given time.

5. Taps number.

6. Vector group or connection way.

7. Winding conductor material.

8. Insulation class.

9. Protection degree.

Meanwhile, we also need to know your load equipment basic specifications.

1. Load type or name.

2. Load start-up mode. Direct start-up or soft start with variable frequency drive (VFD).

Note: Direct starting current of induction motor is as high as 5 to 7 times the normal full load current.

3. Load power rating or capacity (kW).

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Preventive Maintenance Checklist

Use the following as a checklist for maintenance of your dry type transformer:

① De-energize the transformer before continuing with cleaning and repairs.

② Check the system for dust or dirt.

③ Vacuum and blow out the dust or dirt with compressed air.

④ Look for discoloration on insulation or parts that could indicate an electrical problem.

⑤ Tighten accessible hardware.

⑥ Install filters at bottom vent ports. Replace often so you don’t restrict inflow of air.

⑦ Re-energize the system to conduct required tests under load.

⑧ Hire a professional to conduct a TTR test if you suspect electrical problems.

⑨ Conduct a Dielectric Absorption Test.

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Applications

Dry type transformers are widely used in-

Chemical, oil and gas industry.

Environmentally sensitive areas (e.g. water protection areas).

Fire-risk areas (e.g. forests).

Inner-city substations.

Indoor and underground substations.

Renewable generation (e.g. off-shore wind turbines).

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Shipping

Lingfran offer following shipping methods for products.

Sea Shipping: To sea port.

Air Shipping: To airport.

Express Shipping: DHL, FedEx, UPS, etc. Door to door service.

Land Shipping: By trucks or trains. 

Air or Express freight is usually the more expensive, but speedier option (typically 3 to 7 Days). Sea or land freight is normally cheaper, but can take longer. The choice really depends on any budget constraints and also how quickly you want the goods.

Please note that with larger systems (ie. where the packed height of an item exceeds 155 cm – the usual cargo height restriction for cargo on a normal passenger aircraft) air freight may not be an available option if the destination airport is not serviced by a dedicated air cargo freighter service.

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