Automatic voltage regulators (AVR) / stabilizers are generally thought of as ferroresonant and tap switching transformer technologies, often referred to by the acronym AVR. There is also now the addition of a new pulse-width-modulated (PWM) electronic voltage regulation technology, sometimes referred to by a similar acronym, EVR, which utilizes special power transistors, IGBTs (insulated gate bi-polar transistors) and microprocessors to modify the sine wave to an optimal wave shape in a manner similar to that of the pulsed-width-modulation in more expensive UPS, but without the batteries. Of the two, EVR is the more precise technology, usable on any kind of load, and in recent years has proven itself even in underdeveloped countries with extremely unstable power. The older ferroresonant or tap-switching technologies are more cost-effective in the very small sizes, up to 1500VA, with the newer PWM IGBT EVR (that is a mouthful of an acronym set, my apologies) becoming decidedly more cost-effective around 2kVA and above. TSi Power Corporation manufactures both kinds of automatic voltage regulators. For the most 'bullet-proof' or 'rock-solid' units, you should consider a combined EVR + isolation transformer unit that will deliver not only precision voltage regulation, but also noise free isolation with a neutral-ground bond on the output of the transformer, essentially recreating an ideal zero volt condition in common-mode, which in turn yields a stable logic reference for microprocessors. Below, that would be the VRp-ILc, ILc-VRp and VRx combination units. VRp stands for voltage regulation with precision, and ILc for isolation (transformer) line conditioner. Some of these are also available in outdoor enclosures. Please look at the features/series table, or at the more detailed descriptions further down, to determine the voltage regulator series you need. In the table, click on the hyperlink bookmark, such as 'SLc,' to go to that voltage regulator series summary. If you then want more detailed specifications, click on the underlined hyperlink. Also, please note that the TSi Power XUPs Series, and Falcon SG Series UPS are both also automatic voltage regulators along with being battery backup systems. Please see the UPS sections of CareBase. Automatic voltage regulators table    Automatic voltage regulator features           Automatic voltage regulator series   VRp SLc FLc ILc-VRp VRp- ILc 3 ph Out- door VRx Out- door VRp-Ilc   PWM precision voltage regulation+/-2.5%       Ferroresonant voltage regulation +/-3%   Tap-switching voltage regulation +/-10% r   Isolation transformer with N-G bond   Dual voltage input/output ~ 115V/230V    Filtering and surge protection   Over-voltage/under-voltage cutoff 3ph   Automatic bypass   Wide voltage input window Automatic voltage regulator series (Click on underlined hyperlink to view brochure/specifications)

Automatic voltage regulators with isolation transformers
(Click on underlined hyperlink to view full brochure / specs PDF)

	FLc ~ single phase Recommended for extreme environments where the load is 1500VA or under and absolute reliability is a must. The FLc voltage regulator / stabilizer can replace a dedicated line and reduce harmonics, while improving system performance. Applications include industrial control equipment and telephone systems, generator/UPS combinations and other types of equipment with high availability and reliability requirements. The FLc Series offers guaranteed constant output voltage via a heavy duty ferroresonant transformer, full isolation with a neutral-to-ground bond, the best surge protection available, excellent noise filtering, as well as excellent reliability. The only caveat with ferroresonant AVR is that they do have a light hum (that's the 'resonant' part of 'ferroresonant' isolation transformer), so, if it will be in an office environment, you may want to consider placing it some distance away from where anyone is normally going to be sitting. FLc-750-1000-1500 ~ 120V, 750VA, 1000VA and 1500VA.
	ILc-VRp ~ single phase The ILc-VRp dual range automatic precision PWM voltage regulator / stabilizer with built-in low-impedance isolation transformer allows trouble-free operation of electronic equipment over a very wide ac voltage range of 120 or 240 vac +/-20% found in many developing countries. Output regulation responds in less than one line cycle and corrects output voltage to +/-2.5% with 20,000 corrections per second. There is no switching of taps or otherwise a break in the power path as continuous PWM (pulsed-width-modulation) switching of the primary winding of a buck-boost transformer leaves the secondary power path intact. ILc-2000-VRp-Dual-Range ~ 120V+240V/115V+230V, 2000VA
VRp-ILc-16500-0338	VRp-Ilc ~ three phase The VRp-ILc automatic precision voltage regulator / stabilizer with built-in low-impedance isolation transformer allows trouble-free operation of electronic equipment over a very wide mains ac voltage range of 400V +/-20% (+/-30% for short durations) found in many developing countries. There is no switching of taps or otherwise a break in the power path thanks to continuous PWM (pulsed-width-modulation) switching of a buck-boost transformer primary winding. Outstanding voltage regulation: under normal input range of 400 vac +/- 20%, output voltage per phase will be 230 vac +/-1% (47 to 63Hz). Units feature an over/under voltage cutoff, with automatic restart when ac mains voltage returns to normal (safe) condition, below 300 vac or above 160 vac. Failsafe: automatic bypass (even during bypass, the over/under voltage protection is active). These units are designed for applications where absolutely safe and precisely regulated ac power is required, such as mobile communications (GSM/satellite/wireless broadband), radio base stations (RBS) /base transmitter stations (BTS), radio / TV broadcasting, transmission sites for backhaul (including microwave links) industrial process controller (PLC), medical (mobile MRI, CT) and laboratory or analytical measurement equipment. VRp-ILc-16500-0338, 16.5kVA, 400V delta input, 230/400V wye output. Other sizes are available for different applications.

Outdoor isolation transformers with voltage regulation
(Click on underlined hyperlink to view full brochure / specs PDF)

Outdoor VRx ~ single phase The TSi Power outdoor VRx precision PWM automatic voltage regulator / stabilizer with optional built-in low-impedance isolation transformer allows trouble-free operation of electronic equipment over a wide mains ac voltage range of 172 to 276V found in many developing countries. There is no switching of taps or otherwise a break in the power path thanks to continuous PWM switching of a buck-boost transformer primary winding. VRx is also designed with a fail-safe automatic bypass which enables the VRx to provide power to the load even in the event of internal failure that may otherwise result in a disruption of power to the load. VRx with optional isolation transformer provides complete isolation from the ac line, with a neutral-to-ground bond to eliminate all surge voltages between neutral and ground. VRx-4400-0455-0460 ~ 220V/230V/240V, 4.4kVA. Other sizes are available for different voltages.

Outdoor VRp-ILc ~ three phase As above three phase VRp-ILc Series, but the unit comes in a specially designed outdoor rated enclosure with multiple air exhaust fans. To maximize cooling, the isolation transformer is housed in an IP23 outer enclosure. Sensitive components are housed in an IP55 inner case. Overall equivalent is to an IP44 (NEMA-3R) enclosure. The automatic bypass assures that connected equipment will not shut down, even if VRp-ILc fails. VRp-ILc is compatible with all loads as it does not switch any components in the power path. VRp-ILc’s ultra-low impedance assures stability even with the most demanding loads. The automatic overvoltage cutoff with automatic restart ensures that operation is off-line during serious overvoltage situations that could damage the system and/or load, and then restarts without intervention when the ac mains voltage returns to the normal operating range. The lightweight, high efficiency outdoor VRp-ILc is easy to install in exterior environments. VRp-ILc-15000-30000-5339 ~ 230V/400V, 15kVA Other sizes are available for different voltages.

Tap switching voltage regulator power conditioner
(Click on underlined hyperlink to view full brochure / specs PDF)

SLc Four stage tap-switching voltage regulator/stabilizer. Recommended for office and other moderate environments where there is a need for line voltage regulation and surge protection. The SLc units offer four stage voltage regulation, good surge protection and noise filtering, quiet operation at an economical price. Applications include photocopiers, telephone, point-of-sale systems, and small refrigerators for medicines in developing countries. SLc-600-1200-1800 ~ 120V ~ 600VA, 1200VA and 1800VA SLc-1100B-2000B ~ 120V ~ 1100VA and 2000VA SLc-600E-1200E-1800E ~ 230V ~ 600VA, 1200VA and 1800VA SLc-1100BE-2000BE ~ 230V ~ 1100VA and 2000VA

TSi Power Book of product specifications and white papers To download the entire "TSi Power Book of Product Specifications and White Papers," right click here, and then in your dialog box > click on 'Save Link As' or similar, then > navigate to a desired folder that you want to save it in, and then > click on 'Save'. Please note: The book is a 14 megabyte Adobe Acrobat .pdf file, so it may take a while to download on a dial-up line. The book is designed with 'bookmarks' tied to it's Table of Contents, and the 'bookmarks' also appear on the left side as you open the pdf. So for browsing the products and spec sheets, the book is actually quite a fast look-up resource once you have it on your desktop.

TSi Power is also a custom (bespoke in the UK) automatic voltage regulator manufacturer.
For your OEM or special applications, please call us.

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