High Voltage VLF Withstand Voltage Test Set, 0.1Hz VLF Generator for Cable On‑Site Acceptance

High Voltage VLF Withstand Voltage Test Set, 0.1Hz VLF Generator for Cable On‑Site Acceptance

Product Description

This series of ultra low frequency and high voltage generators is a core product developed independently, using a 7-inch touch screen, ARM7 microcontroller, high-speed AD acquisition circuit, and equipped with background management software. High cost performance, especially suitable for withstand voltage testing of electrical equipment with large insulation equivalent capacitance (such as power cables, power capacitors, large and medium-sized generators, and motors), meeting the requirements of the power industry standard "General Technical Conditions for Ultra Low Frequency and High Voltage Generators DL/T849.4-2004".

Product Alias

VLF hipot tester / 0.1Hz VLF AC withstand voltage tester / ultra low frequency high voltage generator / VLF cable hipot test set / power cable vlf withstand voltage tester / 0.1Hz very low frequency test instrument

Features

1. Adopting microcontroller control, 7-inch large screen touch operation, imported photoelectric data transmission, digital frequency conversion, automatic testing, real-time Chinese character prompt during the process, and real-time display of output waveform.

2. Drawing inspiration from the design concepts of the United States and Europe, using our company's developed single link structure and imported high permeability iron core production, not only has strong power, high efficiency, and strong carrying capacity, but also has simple wiring, convenient operation, and is not prone to errors, especially reducing the overall weight and making transportation more convenient.

3. Rated voltage: 30KV, 40KV, 50KV, 60KV, 80KV, 90KV, etc. Current, voltage, and waveform data are directly sampled from the high-voltage side, so the data is accurate.

4. Comprehensive protection: multiple protections (overvoltage protection, high and low voltage side overcurrent protection), quick action (during action) ≤ 10ms), the instrument is safe and reliable.

5. Safe and reliable: The controller is connected to the high-voltage generator at low voltage, with imported photoelectric control, ensuring safe and reliable use.

6. Adopting a high and low voltage closed-loop negative feedback control circuit, the output has no capacitance rise effect.

7. Fully equipped: capacitive touch screen, LCD Chinese character display, automatic storage, and automatic printing. In addition, with a U port and upper computer software, experimental data can be uploaded online, making the instrument more complete.

8. The high-voltage output protection resistor is designed within the boosting body, so there is no need to connect another protection resistor outside.

9. Large testing range: 0.1Hz, 0.05Hz, and 0.02Hz multiple frequency selection, with a large testing range.

10. Small size, light weight, convenient transportation, and very conducive to outdoor work.

11. Switching between Chinese and English backend (other languages can also be customized), exporting to multiple countries.

12. Widely used for AC withstand voltage testing of large capacity equipment such as generators, cables, and power containers

Product Parameters

Application Scenarios

FAQ

Question 1: What main functions can this portable VLF ultra‑low frequency AC hipot tester realize?
Manufacturer: This portable VLF high voltage test device works on 0.1Hz ultra‑low frequency principle. It is mainly applied for AC withstand voltage insulation test of medium‑voltage power cables, generators and other capacitive equipment. It can detect insulation aging, cracks and hidden defects of tested objects. It supports automatic voltage boost, equipped with over‑voltage, over‑current and flashover protection. It can store and print test reports. Widely used for cable factory outgoing inspection, substation on‑site acceptance and regular preventive insulation test.
Question 2: What preparation work should be completed before carrying out VLF withstand voltage test for power cable?
Manufacturer: The tested cable must be completely de‑energized and fully discharged. Disconnect all connecting fittings at both cable ends and isolate the cable from other electric equipment. Clean cable terminals to remove dust, moisture and dirt. Place the main unit and high‑voltage components in a safe area and set up safety warning barriers. Inspect high‑voltage cables and accessories for damage. Complete wiring strictly according to the wiring diagram, and make sure no short‑circuit exists before starting formal test.
Question 3: The instrument keeps triggering over‑current protection during voltage boosting, what are the probable causes?
Manufacturer: Repeated over‑current protection is usually caused by the test sample or improper field conditions. Firstly, check if the cable insulation has serious defects or breakdown risk. Confirm high‑voltage wiring does not touch ground or metal frames. Inspect whether damp or contaminated cable terminals cause surface creepage. Slow down the boosting speed appropriately. If protection still trips, stop the test and check cable insulation status, do not force to continue the test.
Question 4: What are the advantages of 0.1Hz VLF test compared with power‑frequency AC withstand voltage test?
Manufacturer: This VLF tester features compact size and light weight, easy for transportation to outdoor job sites. The 0.1Hz ultra‑low frequency high‑voltage output can achieve equivalent insulation test effect for power cables. It greatly reduces the capacity requirement for on‑site testing, which is very suitable for long large‑capacitance power cables. Meanwhile, it brings less extra damage to intact cable insulation compared with DC hipot test.
Question 5: What critical safety operations shall we follow in VLF high‑voltage withstand voltage test?
Manufacturer: All operators must comply with high‑voltage safety specifications. Build obvious safety warning barriers and keep irrelevant personnel far away from the test zone. After test finishes, perform sufficient multiple discharges on the tested cable before touching cable terminals. Never disconnect any wiring before full discharge is completed. Ensure reliable ground connection all through the whole test process. Avoid outdoor high‑voltage test under rainy or heavy‑humidity weather conditions.
Question 6: If we place an order, how do you typically ship the goods? Will there be any issues with transporting bulky items such as reactors?
Manufacturer: We default to using dedicated logistics lines or brand-specific express shipping services; small-sized main units and accessories may also be shipped via standard courier services. Large items, such as reactors and excitation transformers, are packed using wooden crates or wooden frames for reinforcement to prevent bumps and moisture exposure during transit; a packing list is included with each package to facilitate item-by-item counting for you. Logistics costs are typically determined by both parties in accordance with the contract terms; after shipment, we will send you both the tracking number and the carrier's contact phone number for easy tracking.If your project site is remote or if delivery to the site is required with a specified logistics company, please inform us in advance when placing your order; we can then coordinate and arrange accordingly.
Question 7: Our project is under tight deadlines; how long will it take for the order to be shipped after we place it? Can we request expedited shipping?
Manufacturer: Standard specifications – stock available; typically delivered upon receipt of the order. Orders can be shipped within [X] working days; for non-standard products requiring customized voltage levels, capacities, or reactor combination configurations, the production cycle typically ranges from [X] to [Y] days.The delivery time will be approximately 7-15 working days; the specific timeline shall be subject to the sales confirmation provided upon order placement. If your project has a tight schedule, please inform us of the latest expected delivery date before placing your order; we will first verify the production schedule and inventory status, and where possible, will coordinate expedited production and prioritize shipment. However, it is recommended to allocate sufficient transit time for logistics to avoid delaying on-site testing.
Question 8: What is the warranty period for this equipment? If any issues arise during on-site use, how will your after-sales service respond?
Manufacturer: We provide a two-year free warranty on the entire unit and lifelong technical support services. During the warranty period, if issues arise due to defects in the equipment itself, we will provide free repair or replacement of components; when problems occur on-site, we commit to responding within 24 hours; most wiring and parameter configuration issues can be resolved through remote guidance via video or telephone; for cases where an on-site visit is necessary, we will arrange for our technicians to arrive at the location to resolve the issue. After the warranty period expires, we still offer repair services, with spare parts supplied at cost price for the long term, and software updates provided free of charge for life. Upon delivery of the equipment, we also offer free operational training (video operation guides)to ensure that your testing personnel can operate the equipment independently and proficiently; should you have any further questions, please feel free to contact our dedicated after-sales hotline directly.
Question 9: Our projects are distributed across several states, and our procurement volumes are substantial; are the shipping methods consistent across all states? How is the delivery time calculated?
Manufacturer: The specifications are identical; however, it should be specifically noted that this equipment set is large in size and heavy in weight—components such as the reactor and excitation transformer are all classified as heavy components. Therefore, regardless of which state or region the shipment is destined for, we will uniformly utilize sea freight transportation. The packaging employs export-grade wooden crates with reinforced structures, along with moisture-proof and rust-proof treatments; the design of these wooden crates is optimized for long-distance sea transport and multiple lifting and transshipment operations. Upon arrival at the destination, simply unpack the goods and conduct an inspection before putting them into use. Regarding delivery time, the sea freight transit period depends on the port of destination: near-sea routes are generally faster, whereas ocean routes may take longer; the exact number of days will be confirmed based on the shipping schedule specified in the bill of lading. We have a dedicated freight forwarding agency to handle booking of shipping space, customs declaration, insurance, and other related procedures; once the vessel departs, we will send you documents such as the bill of lading and the packing list, enabling you to arrange for the receipt of goods at the port of destination and their inland transshipment in advance

Shipping scenario

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