Transformers Components manufactures a complete product range of expulsion fuses for use in oil-filled distribution transformers.
ERMCO manufactures a complete product line of expulsion fuses for use in oil-filled distribution transformers. Mounting options include installation inside the high voltage pole transformer bushing and installation using a terminal board.
Three types of fuse cartridge elements are available:
The Current “Fault” Sensing Fuse (catalog numbers 9F54MFC—) is sensitive to current only and offers protection to the primary circuit from transformer faults.
To avoid closing on a fault an Isolation Link or a current limiting fuse must be used in series with the Bayonet Fuse. The current limiting fuse is required when the available fault current exceeds the interrupting rating of the Bayonet Fuse.
| Part Number | Fuse Curve | Amp Rating |
| 9F54MFC040 | C04 | 6 |
| 9F54MFC060 | C06 | 10 |
| 9F54MFC080 | C08 | 15 |
| 9F54MFC100 | C10 | 25 |
| 9F54MFC120 | C12 | 40 |
| 9F54MFC140 | C14 | 65 |
| 9F54MFC160 | C16 | 100 |
| 9F54MFC170 | C17 | 140 |
The Dual Sensing Fuse (catalog numbers 9F54LFC—) is sensitive to both current and oil temperature, thus providing both overload and primary circuit protection.
To avoid closing on a fault an Isolation Link or a current limiting fuse must be used in series with the Bayonet Fuse. The current limiting fuse is required when the available fault current exceeds the interrupting rating of the Bayonet Fuse.
| Part Number | Fuse Curve | Amp Rating |
| 9F54LFC030 | C03 | 3 |
| 9F54LFC050 | C05 | 8 |
| 9F54LFC080 | C08 | 15 |
| 9F54LFC100 | C10 | 25 |
| 9F54LFC120 | C12 | 50 |
The Dual Element Fuse (catalog numbers 9F54DFC—) excels at sensing oil temperature, as well as extreme load currents, secondary faults, and transformer faults. The dual element fuse will reduce the heating time in a transformer caused by overloads and extreme temperature conditions.
To avoid closing on a fault an Isolation Link or a current limiting fuse must be used in series with the Bayonet Fuse. The current limiting fuse is required when the available fault current exceeds the interrupting rating of the Bayonet Fuse.
| Part Number | Fuse Curve | Amp Rating |
| 9F54DFC030 | C03 | 5 |
| 9F54DFC040 | C04 | 6 |
| 9F54DFC050 | C05 | 8 |
| 9F54DFC060 | C06 | 12 |
| 9F54DFC070 | C07 | 15 |
| 9F54DFC090 | C09 | 25 |
| 9F54DFC110 | C11 | 40 |
| 9F54DFC120 | C12 | 50 |
| 9F54DFC140 | C14 | 65 |
The ECI Isolation Link adds a critical layer of protection when paired with Bay-O-Net fuses, preventing accidental re-energization after transformer failure. Built for reliability, it melts under fault conditions, keeping crews safe and systems secure. It’s a simple safeguard for modern pad- and vault-type transformers.
| Fuse Type | Fuse Link Part Number | Isolation Link Part Number | Curve Number |
| Dual Element Fuses | 9F54DFC030 | 7580ZB0299 | A1 |
| Dual Element Fuses | 9F54DFC040 | 7580ZB0299 | A1 |
| Dual Element Fuses | 9F54DFC050 | 7580ZB0399 | A2 |
| Dual Element Fuses | 9F54DFC060 | 7580ZB0399 | A2 |
| Dual Element Fuses | 9F54DFC070 | 7580ZB0399 | A2 |
| Dual Element Fuses | 9F54DFC090 | 7580ZB0499 | A3 |
| Dual Element Fuses | 9F54DFC110 | 7580ZB0499 | A3 |
| Dual Element Fuses | 9F54DFC120 | 7580ZB0499 | A3 |
| Dual Element Fuses | 9F54DFC140 | 7580ZB0599 | A5 |
| Fuse Type | Fuse Link Part Number | Isolation Link Part Number | Curve Number |
| Fault Sensing Fuse Link | 9F54MFC040 | 7580ZB0299 | A1 |
| Fault Sensing Fuse Link | 9F54MFC060 | 7580ZB0399 | A2 |
| Fault Sensing Fuse Link | 9F54MFC080 | 7580ZB0399 | A2 |
| Fault Sensing Fuse Link | 9F54MFC100 | 7580ZB0499 | A3 |
| Fault Sensing Fuse Link | 9F54MFC120 | 7580ZB0499 | A3 |
| Fault Sensing Fuse Link | 9F54MFC140 | 7580ZB0499 | A3 |
| Fault Sensing Fuse Link | 9F54MFC160 | 7580ZB0599 | A5 |
| Fault Sensing Fuse Link | 9F54MFC170 | 7580ZB0599 | A5 |
| Fuse Type | Fuse Link Part Number | Isolation Link Part Number | Curve Number |
| Load Sensing Fuse Link | 9F54LFC030 | 7580ZB0299 | A1 |
| Load Sensing Fuse Link | 9F54LFC050 | 7580ZB0399 | A2 |
| Load Sensing Fuse Link | 9F54LFC080 | 7580ZB0499 | A3 |
| Load Sensing Fuse Link | 9F54LFC100 | 7580ZB0599 | A5 |
| Load Sensing Fuse Link | 9F54LFC120 | 7580ZB0699 | A6 |
| Load Sensing Fuse Link | N/A | 7580ZB0799 | A7 |
The ECI Isolation Link adds a critical layer of protection when paired with Bayonet fuses, preventing accidental re-energization after transformer failure. Built for reliability, it melts under fault conditions, keeping crews safe and systems secure. It’s a simple safeguard for modern pad and vault-type transformers.
| Part Number | Terminal 1 | Terminal 2 | Max Design KV | Amp Range |
| 9F54DAxxx1 | .28 dia hole, weld screw, .250-20 | — | 5.2 | 3–57 |
| 9F54DBxxx1 | .28 dia hole, weld screw, .250-20 | — | 8.4 | 3–48 |
| 9F54DCxxx1 | .28 dia hole, weld screw, .250-20 | — | 23 | 3–28 |
| 9F54DCxxx2 | .28 dia hole | .28 dia hole | 23 | 3–28 |
| 9F54DDxxx1 | .28 dia hole, weld screw, .250-20 | — | 15 | 3–28 |
| 9F54DDxxx2 | .28 dia hole | .28 dia hole | 15 | 3–28 |
| 9F54WLDxxx | .260 dia hole | Cable | 15 | 24–104 |
| 9F54WLDxxx | .260 dia hole | Cable | 15 | 24–104 |
| 9F54ECxxx1 | .343 dia hole, 5/16-18 UNC-2A weld screw | — | 23 | 3–28 |
| 9F54ECxxx2 | .343 dia hole | .343 dia hole | 23 | 3–28 |
| 9F54EAxxx1 | .343 dia hole, 5/16-18 UNC-2A weld screw | — | 5.2 | 3–57 |
| 9F54EAxxx2 | .343 dia hole | .343 dia hole | 5.2 | 3–57 |
| 9F54EBxxx1 | .343 dia hole, 5/16-18 UNC-2A weld screw | — | 8.4 | 3–48 |
| 9F54EBxxx2 | .343 dia hole | .343 dia hole | 8.4 | 3–48 |
| 9F54GCXXX2 | .390 dia hole | .390 dia hole | 23 | 3–28 |
| 9F54GDXXX2 | .390 dia hole | .390 dia hole | 15 | 3–28 |
ERMCO manufactures a complete product line of expulsion fuses for use in oil filled distribution transformers. Mounting options include installation inside the high voltage pole transformer bushing and installation using a terminal board.
ERMCO Components manufactures the 8.3kV/15kV oil-immersed expulsion fuses
for mounting on distribution transformer bushings. These weak link fuses are designed for
application in the primary circuit of a distribution transformer. The purpose of the weak link fuse
is to protect the power system from a faulty distribution transformer by isolating it from the
system.
| Max Interrupting Rating | |||
| (asym. rms amps) | |||
| Product Number | @ 8.3 KV @ 15 KV | Curve | Amps |
| 9F54VDE104 | 3500 2000 | V1 | 4 |
| 9F54VDE204 | 3500 2000 | V2 | 5 |
| 9F54VDE304 | 3500 2000 | V3 | 6 |
| 9F54VDE404 | 3500 2000 | V4 | 7 |
| 9F54VDE504 | 3500 2000 | V5 | 10 |
| 9F54VDE604 | 3500 2000 | V6 | 12 |
| 9F54VDE704 | 3500 2000 | V7 | 14 |
| 9F54VDE804 | 2000 2000 | V8 | 17 |
| 9F54VDE904 | 2000 2000 | V9 | 20 |
Browse our complete selection of single-phase padmount, single-phase polemount, three-phase padmount, and three-phase polemount transformers today.
