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50 Products

About AC to AC Voltage Transformers

For single-phase equipment, use this formula to find power output: VA = Volts × Amps

For three-phase equipment, use this formula to find power output: VA = Volts × Amps × 1.73

Single Phase with Plug and Socket

Single Phase

These transformers have isolated primary and secondary coils to protect your sensitive equipment from input voltage spikes.

Sealed coils and cores prevent corrosion and insulation damage.

When wired as constant voltage transformers, they filter out voltage spikes and electrical noise.

Single Phase—Plug Input and Socket Output

NEMA 5-15 Plug

NEMA 5-15 Socket

Voltage
Input	Output	Power Output, VA	Input Plug Type (NEMA Style)	Output Socket Type (NEMA Style)	Ht.	Wd.	Dp.	Features		Each
Constant Voltage
115V AC	115V AC	150	Three Prong (5-15)	Three Slot (5-15)	3.9"	3.1"	4.2"	Isolated Coils	00000000	0000000
115V AC	115V AC	250	Three Prong (5-15)	Three Slot (5-15)	4.7"	3.8"	4.4"	Isolated Coils	00000000	000000
115V AC	115V AC	500	Three Prong (5-15)	Three Slot (5-15)	4.7"	3.8"	6"	Isolated Coils	00000000	000000
115V AC	115V AC	1,000	Three Prong (5-15)	Three Slot (5-15)	5.3"	4 1/2"	8.1"	Isolated Coils	00000000	000000

Single Phase—Wire Leads Input and Output

Voltage
Input	Output	Power Output, VA	Ht.	Wd.	Dp.	Features	Environment	Environmental Rating	Specifications Met		Each
Step Up/Step Down/Constant Voltage
120V AC, 240V AC	120V AC, 240V AC	1,000	10 1/2"	5 1/2"	5.1"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, C-UL Listed	0000000	0000000
120V AC, 240V AC	120V AC, 240V AC	2,000	13"	5 1/2"	5.1"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, C-UL Listed	0000000	000000
120V AC, 240V AC	120V AC, 240V AC	3,000	11 1/2"	10.3"	7.1"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, C-UL Listed	0000000	000000
120V AC, 240V AC	120V AC, 240V AC	5,000	14.4"	10.3"	7.1"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, C-UL Listed	0000000	00000000
Step Down/Constant Voltage
240V AC, 480V AC	120V AC, 240V AC	750	11.3"	5.3"	6 1/2"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, C-UL Listed	0000000	000000
240V AC, 480V AC	120V AC, 240V AC	1,000	11.3"	5.3"	6 1/2"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, C-UL Listed	0000000	000000
240V AC, 480V AC	120V AC, 240V AC	1,500	13.3"	6.3"	7.8"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, C-UL Listed	0000000	000000
240V AC, 480V AC	120V AC, 240V AC	3,000	13.3"	6.3"	7.8"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, C-UL Listed	0000000	000000
240V AC, 480V AC	120V AC, 240V AC	5,000	15"	10.2"	10.6"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, C-UL Listed	0000000	000000
240V AC, 480V AC	120V AC, 240V AC	7,500	15.2"	13 1/2"	10.8"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, CSA Certified	0000000	00000000
240V AC, 480V AC	120V AC, 240V AC	10,000	15.2"	13 1/2"	10.8"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, CSA Certified	0000000	00000000
240V AC, 480V AC	120V AC, 240V AC	15,000	16.9"	14.1"	11.6"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, CSA Certified	0000000	00000000
240V AC, 480V AC	120V AC, 240V AC	25,000	18.4"	16.1"	13.3"	Isolated Coils, Sealed Coils, Sealed Cores	Outdoor	NEMA 3R	UL Listed, CSA Certified	0000000	00000000

Enclosed Voltage-Stabilizing AC to AC Transformers

Protect sensitive equipment from electromagnetic interference and maintain power during three-millisecond power dips. These transformers also isolate output and input voltage (output regulation is ±3% with input voltage fluctuations from +10% to -20%). When wired for constant voltage, transformers filter out voltage spikes and electrical noise.

Voltage
Input	Output	Power Output, VA	Ht.	Wd.	Dp.	Specifications Met		Each
Single Phase—Screw Terminals Input and Output
Step Up/Step Down/Constant Voltage
120V AC, 208V AC, 240V AC, 480V AC	120V AC, 208V AC, 240V AC	140	4.4"	6"	8 1/2"	UL Listed, CSA Certified	0000000	0000000
120V AC, 208V AC, 240V AC, 480V AC	120V AC, 208V AC, 240V AC	250	4.4"	6"	9.7"	UL Listed, CSA Certified	0000000	000000
120V AC, 208V AC, 240V AC, 480V AC	120V AC, 208V AC, 240V AC	500	6 1/2"	6.3"	12.3"	UL Listed, CSA Certified	0000000	00000000
120V AC, 208V AC, 240V AC, 480V AC	120V AC, 208V AC, 240V AC	750	6 1/2"	6.3"	13.3"	UL Listed, CSA Certified	0000000	00000000
120V AC, 208V AC, 240V AC, 480V AC	120V AC, 208V AC, 240V AC	1,000	6 1/2"	6.3"	14.2"	UL Listed, CSA Certified	0000000	00000000
120V AC, 208V AC, 240V AC, 480V AC	120V AC, 208V AC, 240V AC	1,500	9.9"	9.4"	17.6"	UL Listed, CSA Certified	0000000	00000000
120V AC, 208V AC, 240V AC, 480V AC	120V AC, 208V AC, 240V AC	3,000	9.9"	9.4"	19.9"	UL Listed, CSA Certified	0000000	00000000

Touch-Safe High-Inrush Panel-Mount AC to AC Transformers

Prevent accidental contact with live electrical connections—the screw terminals are covered or recessed. These transformers can handle momentary high-inrush current associated with contactors, solenoids, and relays. Also known as control transformers.

When wired for constant voltage, transformers filter out voltage spikes and electrical noise.

Voltage
Input	Output	Power Output, VA	Ht.	Wd.	Dp.	Features	Specifications Met		Each
Single Phase—Screw Terminals Input and Output
Step Down/Constant Voltage
230V AC/460V AC/575V AC	24V AC/115V AC/230V AC	250	4"	4 1/2"	4.8"	Covered Terminals	UL Listed, C-UL Listed, CE Marked	0000000	0000000
230V AC/460V AC/575V AC	24V AC/115V AC/230V AC	300	4"	4 1/2"	5.3"	Covered Terminals	UL Listed, C-UL Listed, CE Marked	0000000	000000
230V AC/460V AC/575V AC	24V AC/115V AC/230V AC	350	4 1/2"	5.3"	5.4"	Covered Terminals	UL Listed, C-UL Listed, CE Marked	0000000	000000
230V AC/460V AC/575V AC	24V AC/115V AC/230V AC	500	4 1/2"	5.3"	6.6"	Covered Terminals	UL Listed, C-UL Listed, CE Marked	0000000	000000
230V AC/460V AC/575V AC	24V AC/115V AC/230V AC	750	6"	6.4"	7.4"	Covered Terminals	UL Listed, C-UL Listed, CE Marked	0000000	000000
230V AC/460V AC/575V AC	24V AC/115V AC/230V AC	1,000	6.3"	6.8"	7.8"	Covered Terminals	UL Listed, C-UL Listed, CE Marked	0000000	000000

Bench-Top Variable-Voltage AC to AC Transformers

NEMA 5-15 Plug

NEMA 5-15 Socket

NEMA 5-20 Plug

NEMA 5-20 Socket

NEMA 6-15 Socket

NEMA 6-15 Plug

Mount these portable transformers to any flat surface. Turn the dial to adjust the voltage you need within a given range. Also known as variacs, they are often used in laboratories to vary power, heat, speed, or force.

When wired for constant voltage, transformers filter out voltage spikes and electrical noise.

Voltage
Input	Output	Power Output, VA	Max. Current, A	Input Plug Type (NEMA Style)	Input Cord Lg., ft.	Output Socket Type (NEMA Style)	Ht.	Wd.	Dp.	Features	Specifications Met		Each
Single Phase—Plug Input and Socket Output
Step Up/Step Down/Constant Voltage
120V AC	0V AC-132V AC	330	2.5	Three Prong (5-15)	6	Three Slot (5-15)	5.3"	6.1"	4.1"	Fuse, Power-Indicating Light	CSA Certified	0000000	0000000
120V AC	0V AC-140V AC	700	5	Three Prong (5-15)	6	Three Slot (5-15)	5.3"	6.1"	4.1"	Fuse, Power-Indicating Light	__	0000000	000000
120V AC	0V AC-140V AC	1,400	10	Three Prong (5-15)	6	Three Slot (5-15)	7"	4.6"	5.5"	Fuse, Power-Indicating Light	CSA Certified	0000000	000000
120V AC	0V AC-140V AC	2,100	15	Three Prong (5-15)	6	Three Slot (5-15)	9.4"	6.2"	6"	Fuse, Power-Indicating Light	CSA Certified	0000000	00000000
120V AC	0V AC-140V AC	3,080	22	Three Prong (5-20)	6	Three Slot (5-20)	10.9"	8"	6.3"	Fuse, Power-Indicating Light	__	0000000	00000000
240V AC	0V AC-280V AC	980	3.5	Three Prong (6-15)	6	Three Slot (6-15)	7"	4.6"	5.5"	Fuse, Power-Indicating Light	__	0000000	000000
240V AC	0V AC-280V AC	2,660	9.5	Three Prong (6-15)	6	Three Slot (6-15)	9.4"	6.2"	6"	Fuse, Power-Indicating Light	__	0000000	00000000
Step Down/Constant Voltage
120V AC	0V AC-120V AC	1,440	12	Three Prong (5-15)	6	Three Slot (5-15)	7"	4.6"	5.5"	Fuse, Power-Indicating Light	CSA Certified	0000000	000000
240V AC	0V AC-240V AC	1,200	5	Three Prong (6-15)	6	Three Slot (6-15)	7"	4.6"	5.5"	Fuse, Power-Indicating Light	CSA Certified	0000000	000000

Panel-Mount Variable-Voltage AC to AC Transformers

Permanently install these transformers in panels. Turn the dial to adjust the voltage you need within a given range. Also known as variacs, they are often used in laboratories to vary power, heat, speed, or force. When wired for constant voltage, transformers filter out voltage spikes and electrical noise.

Voltage
Input	Output	Power Output, VA	Max. Current, A	Quick-Disconnect Tab Wd.	Ht.	Wd.	Dp.	Specifications Met		Each
Single Phase—Quick-Disconnect Terminals Input and Output
Step Down/Constant Voltage
120V AC	0V AC-120V AC	210	1.75	0.25"	3.3"	2.9"	1.9"	CSA Certified	0000000	0000000
120V AC	0V AC-120V AC	300	2.5	0.25"	3.3"	2.9"	2.1"	CSA Certified	0000000	000000
120V AC	0V AC-120V AC	360	3	0.25"	3.3"	2.9"	2.4"	CSA Certified	0000000	000000
120V AC	0V AC-120V AC	600	5	0.25"	4.4"	3.8"	3"	CSA Certified	0000000	000000
Single Phase—Screw Terminals Input and Output
Step Down/Constant Voltage
120V AC	0V AC-120V AC	1,200	10	__	5.6"	4.4"	4.2"	CSA Certified	0000000	000000
120V AC	0V AC-120V AC	1,440	12	__	5.6"	4.4"	4.2"	CSA Certified	0000000	000000
120V AC	0V AC-120V AC	1,800	15	__	6.8"	6.1"	4.3"	CSA Certified	0000000	000000
120V AC	0V AC-120V AC	3,000	25	__	8.3"	7.6"	4.4"	CSA Certified	0000000	00000000
240V AC	0V AC-240V AC	1,200	5	__	5.6"	4.4"	4.2"	CSA Certified	0000000	000000
240V AC	0V AC-240V AC	2,280	9.5	__	6.8"	6.1"	4.6"	CSA Certified	0000000	000000
Step Up/Step Down/Constant Voltage
240V AC	0V AC-280V AC	980	3.5	__	5.6"	4.4"	4.2"	CSA Certified	0000000	000000

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About AC to AC Voltage Transformers

Enclosed Isolating AC to AC Transformers

Enclosed Voltage-Stabilizing AC to AC Transformers

Touch-Safe High-Inrush Panel-Mount AC to AC Transformers

Bench-Top Variable-Voltage AC to AC Transformers

Panel-Mount Variable-Voltage AC to AC Transformers