Low Frequency Transformers: Key Features & Industrial Application

 Low frequency transformers are essential power‑handling components widely used in power supply systems, industrial equipment, and isolation power scenarios. Designed to work under mains‑level low‑frequency conditions, these transformers focus on stable voltage conversion, electrical isolation and noise suppression.

Different from high‑frequency switching transformers such as the flyback transformers, low frequency transformers usually adopt silicon‑steel laminated cores, delivering high reliability for long‑time continuous operation.

They are commonly seen in UPS power supplies, industrial control cabinets, medical isolation power units and household power‑isolation devices.

While flyback designs dominate many compact SMPS power adapters working at high kHz range, low frequency transformers operate at 50‑60Hz grid frequency for heavy‑duty isolation and power transformation tasks.

When selecting proper low frequency transformers, users need to consider rated power, input‑output voltage ratio, isolation requirements and installation dimensions. Custom winding solutions are available for special‑specification industrial projects.

Proper core material selection directly affects working efficiency and heating performance. Silicon steel core remains the mainstream choice for low‑frequency transformer manufacturing for its good magnetic‑conducting property at 50/60Hz.

Item	Core Type	Output Power(w)	Item	Core Type	Output Power(w)
EI28	EI28/8*12	0.5-1	EI57	EI57/19*30	16-32
EI28	EI28/8*16	0.7-1	EI57	EI57/19*38	20-40
EI35	EI35/9.6*10	0.2-0.8	EI66	EI66/22*22	17-35
EI35	EI35/9.6*12.5	0.25-1	EI66	EI66/22*28	24-45
EI35	EI35/9.6*16	0.4-1.7	EI66	EI66/22*35	36-58
EI35	EI35/9.6*20	0.6-2.5	EI66	EI66/22*45	55-77
EI41	EI41/13*13	0.6-2.3	EI76	EI76.2/25.4*25	65-88
EI41	EI41/13*16	1-3.6	EI76	EI76.2/25.4*31.5	71-95
EI41	EI41/13*21	1.6-5.5	EI76	EI76.2/25.4*40	70-97
EI41	EI41/13*26	2.3-7.7	EI76	EI76.2/25.4*50	86-123
EI48	EI48/16*16	2-5	EI85.8	EI85.8/28.6*29	70-95
EI48	EI48/16*20	2.8-7.2	EI85.8	EI85.8/28.6*36	84-120
EI48	EI48/16*25	4.6-11.1	EI85.8	EI85.8/28.6*46	105-154
EI48	EI48/16*32	7-10	EI85.8	EI85.8/28.6*58	130-200
EI54	EI54/18*18	5-12	EI96	EI96/32*40	100-150
EI54	EI54/18*22.5	8-17	EI96	EI96/32*45	110-160
EI54	EI54/18*29	11-25	EI105	EI105/35	500-700
EI54	EI54/18*36	17-34	EI114	EI114/38	700-1000
EI57	EI57/19*19	7-16
EI57	EI57/19*24	14-21

When you are working on large‑scale industrial power‑distribution systems with multi‑phase power input, three‑phase isolation transformers become a critical hardware choice. Read our article Three Phase Transformer for Industrial Power Distribution | Custom KVA Ratings to view full technical parameters and custom‑build support.