Stepping primary utility power down to low-voltage control circuits without adding secondary power conversion hardware keeps control panels simple and reliable. Direct step-down transformers solve this by converting 480 VAC utility power straight to a 24 VAC control bus—without extra DIN-rail power supplies or unnecessary heat buildup.
Compact Control Hardware: Marcus MTC100-35-MTB
Deploying a dedicated step-down transformer lets you power relays, contactor coils, and pilot lights directly inside your electrical cabinet.
100 VA Power Rating & Single-Stage Step-Down: Converts standard 480 VAC primary input directly down to a 24 VAC secondary output at 60 Hz. Delivering up to 100 VA of continuous apparent power, it handles a low continuous input current (~0.208 A) while supplying up to 4.17 A on the secondary side to energize multiple control devices simultaneously.
Molded Barrier Terminal Block (MTB): Features molded insulating barriers between adjacent Robertson-head terminal screws. This design isolates wire terminals to prevent phase-to-phase short circuits caused by stray wire strands or heavy machine vibration on the plant floor.
Hardware Overview
| Feature | Marcus MTC100-35-MTB |
| Capacity | 100 VA (Continuous Output) |
| Primary Voltage | 480 VAC (60 Hz) |
| Secondary Voltage | 24 VAC (~4.17 A Output) |
| Terminal Protection | Molded Barrier Screw Block |
| Conductor Material | High-Conductivity Copper Magnet Wire |
| Insulation / Temp Rise | Class B 130°C Insulation (80°C Thermal Rise) |
| Compliance | Dual UL Listed & CSA Approved |
Built-In Thermal Stability and Code Compliance
System installation is straightforward with an open core-and-coil frame that fits standard control panel footprints.
Because this transformer uses high-permeability silicon steel laminations and solid copper windings, it limits core losses while maintaining stable voltage under heavy inductive loads. Natively meeting standard cabinet safety requirements, it provides:
- Inrush surge protection: Sustains temporary current surges when contactor coils energize without causing secondary voltage drops.
- Natural convection cooling: Dry-type design eliminates liquid fluid maintenance and seal leak risks.
- Full safety approvals: Dual UL Listing and CSA Approval for passing electrical panel inspections.
Practical Field Applications
From stepping down incoming power in industrial motor control centers to driving 24V relay logic in machine automation cabinets, this standalone transformer streamlines low-voltage power distribution. By consolidating voltage reduction into a single component, you save mounting space, lower internal cabinet heat, and maintain steady system uptime without complex wiring setups.