Isolation & Special-Duty Transformers
JMB Portable Work-Light Transformer
Some job sites don’t just need power — they need power that can’t hurt anyone if something goes wrong. Inside a metal tank, a boiler, a damp tunnel, or any confined conductive space, a fault on a standard 220V hand lamp can be lethal, which is why site-safety practice calls for portable lighting to run on safety extra-low voltage instead of mains voltage. The JMB series steps supply voltage down to exactly that: 220V or 380V input converts to 6V, 12V, 24V, or 36V output — low enough that even direct contact isn’t dangerous, not just isolated from a fault the way a standard isolation transformer is. Quick-connect terminals let a lamp or hand tool be plugged in and unplugged on site without rewiring, a multi-face heat-dissipation grille keeps the case cool under repeated on/off cycling in the field, and the core is wound on imported silicon steel sheet for consistent electromagnetic performance. The range runs from a compact 50-100VA unit for a single lamp circuit to an 8000-10000VA model for larger site power needs, with other primary and secondary voltage combinations available on request.
Key Features
Built to Make Contact Safe, Not Just Isolated
JMB steps voltage down to safety extra-low voltage levels for confined, damp, or metal-enclosed work environments, rather than relying on isolation alone.
Safety Extra-Low Voltage Output
Steps 220V/380V mains down to 6V, 12V, 24V, or 36V — voltage low enough to be inherently safe on contact.
Built for Confined, Damp Sites
Suited to metal tanks, boilers, tunnels, and other conductive or damp environments where standard voltage is a hazard.
Quick-Connect Terminals
Clearly marked terminals let a lamp or hand tool be plugged in and unplugged on site without rewiring.
Multi-Face Heat Dissipation Grille
Ventilation on multiple sides lowers operating heat and supports repeated on/off cycling in the field.
Imported Silicon Steel Core
Electrical-grade silicon steel sheet core for consistent electromagnetic performance.
50-10000VA Range
From a single-lamp-circuit unit to larger site-power builds, with custom voltage combinations available.
OEM & ODM Capabilities
Built-to-Order for B2B and System Integrators
Capacity, voltage combination, and terminal layout are configured for the specific site or job requirement.
Configurable Capacity
Standard range 50-10000VA, with custom builds available beyond the standard sizes.
Primary/Secondary Voltage Customization
Input from 220V or 380V, output from 6.3V up to 380V, or another combination specified at order time.
Terminal Layout Configuration
Terminal count and labeling adapted to the number of lamp or tool circuits on site.
Enclosure & Branding Customization
Cabinet finish and labeling configurable for private-label and distributor branding.
Application-Specific Configuration
Sized and configured for construction sites, confined-space work, and portable lighting circuits.
Small-to-Large Batch Production
From single-unit orders to volume production for contractors and equipment distributors.
Technical Specifications
Insulation, temperature, and environmental ratings are shared across the JMB series; capacity and dimensions scale by model.
| Product Name | Portable Work-Light Transformer |
|---|---|
| Frequency | 50/60Hz |
| Waveform Distortion | None additional |
| Insulation Resistance | >50MΩ |
| Temperature Rise | ≤60°C |
| Ambient Temperature | -5°C to +40°C (24-hour average below 35°C) |
| Relative Humidity | ≤90% |
| Primary Voltage | 220V / 380V (customizable per requirement) |
| Secondary Voltage | 6.3V / 12V / 24V / 36V / 110V / 127V / 220V / 380V (customizable) |
| Featured Safety Outputs | 6V / 12V / 24V / 36V for portable lighting circuits |
| Capacity Range | 50-10000VA |
| Insulation | >50MΩ |
|---|---|
| Temp Rise | ≤60°C |
| Capacity | 50-10000VA |
| Output | 6-36V (safety) |
| Model | Width (W) | Height (H) | Length (L) |
|---|---|---|---|
| JMB50-100VA | 200mm | 115mm | 120mm |
| JMB150-200VA | 220mm | 130mm | 130mm |
| JMB250-300VA | 240mm | 150mm | 150mm |
| JMB400-600VA | 270mm | 175mm | 170mm |
| JMB700-1000VA | 300mm | 210mm | 180mm |
| JMB1500-2000VA | 350mm | 250mm | 220mm |
| JMB2500-3000VA | 390mm | 250mm | 230mm |
| JMB4000-5000VA | 440mm | 300mm | 280mm |
| JMB8000-10000VA | 490mm | 320mm | 330mm |
Construction & Configuration
An imported silicon steel core sits inside a ventilated steel enclosure with quick-connect terminals for on-site lamp and tool circuits.
Imported Silicon Steel Core
Electrical-grade silicon steel sheet core for the electromagnetic performance the transformer relies on.
Quick-Connect Terminal Panel
Clearly labeled front-panel terminals for plugging in and unplugging lamp or tool circuits on site.
Multi-Face Ventilation Grille
Louvered vents across multiple sides of the enclosure dissipate heat generated during operation.
Compact Steel Enclosure
Portable steel housing sized to be carried and repositioned around a job site.
Safety Extra-Low Voltage Output Configuration
Wound to deliver 6-36V output for lighting circuits, or other secondary voltages up to 380V on request.
9-Step Capacity Range
Nine standard sizes from 50-100VA to 8000-10000VA, scaled in dimension to match rated load.
Standards & Test Documentation
Insulation resistance and temperature rise are confirmed on every unit; further documentation is available for site-safety compliance review.
>50MΩ
Insulation resistance confirmed above 50MΩ on every unit.
≤60°C Temperature Rise
Temperature rise held at or below 60°C under rated operating conditions.
Datasheets & Dimension Drawings
Full parameter sheets and dimensional drawings available on request for site-safety and procurement review.
Need Safe Power for a Confined or Damp Work Site?
Tell us your site conditions and required output voltage — we'll configure a JMB unit or another series to match.