Can Siemens Energy voltage regulators be customized or upgraded?

All our products are customizable and can be upgraded to the extent their components allow.

Voltage regulators

The standard voltage regulator provides approximately 10% adjustment. However, in some designs, regulations of 15% and 20% are also available. Available at 50 or 60 Hz, their ratings are calculated according to the voltage level of the transformer they are connected to (i.e., 10%). Voltage level ratings for 1-phase voltage regulators vary between 2.5kV and 19.9 kV and between 76.2kVA and 1110kVA. 3-phase units are available at 13.2kV, 34.5kV, or from 500kVA up to 4,000kVA.

Siemens Energy invented the voltage regulator in 1932. Voltage regulators are highly reliable soutions for stabilizing voltage fluctions in the customer's grid 24/7. They are notably more cost-effective for customers compared to other oprions. Voltage regulators come in 1-phase or 3-phase models. Different cooling systems are available. They can be applied to any electrical system to improve voltage quality. The standard voltage regulator provides approximately 10% adjustment. However, in some designs, regulations of 15% and 20% are also available. Available at 50 or 60 Hz, their ratings are calculated according to the voltage level of the transformer they are connected to (i.e., 10%). Voltage level ratings for 1-phase voltage regulators vary between 2.5 kV and 19.9 kV and between 31.8 kVA and 889 kVA. 3-phase units are available at 13.2 kV, 34.5 kV, or from 500 kVA up to 4,000 kVA.

JFR and SFR medium-voltage voltage regulators

When it comes to voltage regulation, Siemens Energy provides technology that serves the customer. Our manufacturing experience for voltage regulators and controls is unsurpassed in the industry. Today, Siemens Energy has the largest quantity of regulators installed worldwide. The type JFR has been an industry leader since 1936. It is a single-phase 5/8% step regulator utilizing the Siemens Energy type MJ4 or MJ6 control panel or adaptable to any control panel.

Electrostatically-applied polyester paint provides greater resistance to corrosion in harsh environments.
Type-316 stainless steel external hardware to eliminate rust and galling.
Sealed tank has pressure relief device to vent gases produced during tap changes. The Siemens 55°C rise regulators can be loaded to up to 12 percent above nameplate rating, with the 65°C insulation system.
External metal-oxide varistor (MOV) bypass arrester provides superior protection to the regulator series winding from surge and system transients.
Oil-sight gauge allows oil levels and oil conditions to be checked without de-energizing the regulator.
Motor capacitor installed in the control cabinet allows replacement without bypassing and transitioning the regulator out of service.
Polarized disconnect switch (PDS) facilitates easy control installation of change out without taking the regulator out of service.
Cover-mounted terminal block provides easier access to wiring by eliminating the need to go under the oil to change tap connections.
Monitor and automatically control output voltage through the use of state-of-the-art microprocessor control panels MJ-6.
High-creep bushings provide a minimum creep distance of 17" (432 mm).
Oil-drain valve includes an oil sampling valve for easy access.
Platform base is equipped with provisions to securely attach regulator to sub-base assembly.

Options include:

Stainless-steel tank
Esther fluid
Padmount design
+/- 20% regulation
Heated cabinet
Lightning arresters.

External modifications line terminals:

Special ground pads/connectors
Lowered control enclosure
Special ultra-creep bushings
Thermometers or fans (if possible)
Special drain valves
Nameplate changes/modifications.

Internal modifications:

Source-side potential transformer
Special current transformer.

The Siemens Energy padmount voltage regulator offers a new dimension to underground system planning and design that preserves an aesthetically pleasing environment. Maintaining all of the functionality of a traditional regulator, the padmount voltage regulator promotes safety because there are no exposed high-voltage lines. Additionally, the tamper-resistant, secured cabinet design protects the access to components including the drain valve, bushings and cover bolts. The layout and positioning of the controls is on the narrow end of the box, which allows for additional placement options and smaller operational space requirements. The controls are ergonomically positioned for easy access for operators. The bushing connections and sample valve reside in the lower enclosure. With the Siemens Energy padmount voltage regulator, safety and reliability are enhanced, construction costs are reduced, and land requirements are smaller for a more attractive physical profile for the public.

The type SFR is a vertically integrated, three-phase regulator, which also comes with the capability of separating the tap changer. This significantly increases the life of the regulator. Siemens Energy offers distinct advantages with all of our three-phase regulators engineered and manufactured in-house. Our expertise in both technology and service gives us additional advantages in the custom engineering necessary for most three-phase regulator applications. The SFR voltage regulator has proven its reliability and durability in the toughest environments. Unit construction, tough exterior coating and a side inspection door are just a few of the time-tested features of today’s SFR. Additionally, Siemens Energy offers the popular SFR-X which features a separate tap-changing mechanism compartment allowing for easy inspection and maintenance. Separating the regulator tap-changer significantly increases the life of the regulator by eliminating arcing in the main tank containing the coil and core.

Maximum design voltage kV	Withstand voltage levels lightning impulse (BIL) kV	Load current A	kVA	Catalog number	ONAN/ONAF
5.0	75	346	300	40-5.0-0300	ONAN
5.0	75	866	750	40-5.0-0750	ONAN
13.2	95 or 110	219	500	40-13.2-0500	ONAN
13.2	95 or 110	328	750	40-13.2-0750	ONAN
13.2	95 or 110	437	1,000	40-13.2-1000	ONAN
13.2	95 or 110	656	1,500	40-13.2-1500	ONAN
13.2	95 or 110	874	2,000	40-13.2-2000	ONAN
13.2	95 or 110	1,093	2,500	40-13.2-2500	ONAN
13.2	95 or 110	1,300	2,972	40-13.2-2972	ONAN
13.2	95 or 110	274	625	41-13.2-0625	ONAF
13.2	95 or 110	410	937	41-13.2-0937	ONAF
13.2	95 or 110	546	1,250	41-13.2-1250	ONAF
13.2	95 or 110	874	2,000	41-13.2-2000	ONAF
13.2	95 or 110	1,166	2,667	41-13.2-2667	ONAF
13.2	95 or 110	1,458	3,333	41-13.2-3333	ONAF
13.2	95 or 110	1,750	4,000	41-13.2-4000	ONAF
34.5	200	84	500	40-34.5-0500	ONAN
34.5	200	167	1,000	40-34.5-1000	ONAN
34.5	200	251	1,500	40-34.5-1500	ONAN
34.5	200	335	2,000	40-34.5-2000	ONAN
34.5	200	105	625	41-34.5-0625	ONAF
34.5	200	209	1,250	41-34.5-1250	ONAF
34.5	200	335	2,000	41-34.5-2000	ONAF
34.5	200	446	2,667	41-34.5-2667	ONAF

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A voltage regulator is a device used in electrical distribution systems to maintain a stable output voltage, even when the input voltage fluctuates due to changing load conditions.
Step-type voltage regulators are commonly used by utility companies to improve service quality and optimize energy usage. They adjust voltage levels along distribution lines to either increase or decrease power consumption. For example, raising voltage during off-peak times can boost energy use and revenue, while lowering voltage during peak demand can reduce strain on the system and delay costly infrastructure upgrades.

The main types of voltage regulators include:
• JFR – Single-phase voltage regulator
• SFR – Three-phase voltage regulator
• Padmount – Designed for ground-level installation, often used in urban or residential areas
• MJ and XL Control Panels These are control units that can be purchased separately and used to manage regulator functions
Each type serves different needs depending on the electrical system and installation environment.

A step voltage regulator is a device that automatically maintains a constant voltage level in power distribution systems. It adjusts the voltage—either increasing (stepping up) or decreasing (stepping down)—to compensate for changes in load and input voltage. This ensures that all users along the transmission line receive the correct voltage, improving power quality and protecting equipment from voltage fluctuations.

The single-phase step voltage regulator was invented by Siemens Energy (back then Siemens) in 1932. This invention has since become an industry standard. Our company has played a leading role in advancing voltage regulator technology for over half a century. After time key innovations such as static controls and microprocessor-based control panels were introduced and today the technology offers a wide range of regulator solutions—from small single-phase units to large substation systems. Today Siemens Energy has the largest population of installed regulators worldwide.

Voltage regulators

Voltage regulator: the alternative to grid-expansion

Technology

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