Not every isolation transformer belongs in a clean, climate-controlled electrical room. Outdoor equipment, corrosive facilities, dusty plants, washdown areas,...
Transformer Solutions
for Industrial Automation
Automation systems depend on clean, reliable power. PLCs, servo drives, robotics, and machine controllers are highly sensitive to voltage fluctuations, harmonics, and ground noise — problems that the right transformer solves at the source. Transformer Source supplies control transformers, isolation transformers, and K-factor rated units trusted by machine builders, systems integrators, and automation engineers across North America.
- CSA & UL Certified
- Ships from Canadian Stock
- 3 kVA – 1,000 kVA Range
- Custom Configurations Available
Powering Industrial Automation Systems
Industrial automation puts unique demands on power quality. Servo drives, variable frequency drives, and switch-mode power supplies all generate harmonic distortion that overheats standard transformers and corrupts control signals. At the same time, PLCs, HMIs, and safety controllers require rock-solid isolated control power — any brownout or noise event can trigger faults, halt production, or damage equipment.
Transformer Source supplies the full range of transformer types used in automation: from small control transformers inside machine enclosures to large isolation transformers feeding entire production cells. Our units are machine-tool rated, CSA/UL certified, and built to handle the continuous duty cycles of 24/7 automated production.
Key Automation Power Challenges We Solve:
- Control circuit isolation: Dedicated isolated 120V or 24V power for PLCs, HMIs, and safety relays — independent of main drive power
- Harmonic distortion: K-factor rated units handle non-linear loads from servo drives, VFDs, and switch-mode power supplies without overheating
- Voltage conversion: Connecting imported automation equipment (CE-marked, 230V/400V European or 208V/460V US) to Canadian 600V supply
- Ground noise elimination: Isolation transformers break ground loops that corrupt encoder signals, fieldbus networks, and analog I/O
- Short-circuit protection: Machine-tool rated control transformers with high short-circuit withstand — essential for fault-tolerant machine design
- Compact form factor: Encapsulated and open-frame units sized to fit inside control enclosures and machine cabinets
Automation Applications We Serve:
- Robotic Cells & Welding Automation
- CNC Machine Tools & Machining Centres
- Automated Assembly & Packaging Lines
- Conveyor & Material Handling Systems
- Servo Press & Stamping Automation
- Vision Systems & Quality Inspection
- OEM Machine Builders & Systems Integrators
- Industrial IoT & Smart Factory Infrastructure
- Process Control & SCADA Systems
Recommended Transformers for Industrial Automation
The following transformer types are most commonly specified for automation systems, machine builds, and control panel design. Filter by kVA, voltage, or enclosure using the product search.
Isolation Transformers
3kVA to 750kVA Capacity
Encapsulated Isolation Transformers
0.25kVA to 150kVA Capacity
Autotransformers
3kVA to 1000kVA Capacity
Encapsulated Autotransformers
3kVA to 300kVA Capacity
Control Transformers
25VA to 5000VA Capacity
Motor Starters
10HP to 500HP Capacity
Mini Power Centers
5kVA to 45kVA Capacity
Recommended Specifications for Automation Applications
Use the following as a baseline reference for specifying transformers in automation system design and machine building.
PLC / HMI Control Panel (single machine) | 0.1 – 1 kVA |
Machine Tool Control Circuit | 0.5 – 5 kVA |
Robotic Cell (1–4 robots) | 5 – 30 kVA |
CNC Machining Centre | 5 – 50 kVA |
Automated Packaging Line | 15 – 75 kVA |
Servo Press / Stamping Cell | 30 – 150 kVA |
Full Production Cell (multiple drives) | 50 – 300 kVA |
Imported Machinery (voltage conversion) | Matched to equipment nameplate kVA x 1.25 |
Plant Automation Infrastructure (MCC/drives room) | 150 – 750 kVA |
For imported machinery, always size at 125% of nameplate kVA to account for inrush and future load additions.
Primary (Input) | 600V or 575V, 3-phase (Canadian plant distribution) |
Secondary — Drive Panels | 480V or 208V, 3-phase |
Secondary — Control Circuits | 120V or 24V, single-phase |
European Imported Equipment | 600V → 400V/230V, 3-phase (CE-marked machinery) |
US Imported Equipment | 600V → 460V or 208V, 3-phase |
Asian Imported Equipment | 600V → 200V or 380V, 3-phase |
Taps | ±2.5% and ±5% — critical for fine-tuning voltage at machine terminals |
Open / Panel Mount | Inside control enclosures — control transformers in NEMA 12 or 4 panels |
NEMA 1 | Electrical rooms and clean automation cells |
NEMA 12 (Dust-tight) | Plant floor automation — coolant mist, metal chips, oil aerosols |
NEMA 4 / 4X | Wash-down automation lines — food, beverage, pharmaceutical |
Encapsulated | Harsh wash-down, outdoor automated systems, paint booths |
Inside Machine Enclosure | Control transformers — panel-mount, sized to fit within NEMA 12 or 4 cabinet |
Plant Floor (standalone) | NEMA 12 minimum for open plant environments with coolant and dust |
Dedicated Electrical Room | NEMA 1, serving drive panels and MCCs for automation cells |
Outdoor Automated Systems | Encapsulated or NEMA 3R — outdoor conveyors, storage automation, loading systems |
Clearances | 36″ front, 18″ sides for standalone units — panel-mount units per enclosure design |
Canadian Standard | CSA C22.2 No. 47 — mandatory for all Canadian installations |
Machine Tool Rating | CSA / UL machine tool rated control transformers — required for CNC and machine builder applications |
US Standard | UL 506 / UL 1561 — required for US-shipped machines and equipment |
CE Compliance | Available for machines exported to EU / international markets |
Electrical Code | CEC Part I (Canada) / NEC NFPA 70 (US) |
Safety Standards | Transformer isolation supports IEC 62061 / ISO 13849 machine safety requirements |
K-1 (Standard) | Simple motor loads, resistive heating — not suitable for servo or VFD loads |
K-4 | Light automation with a few small drives or switch-mode power supplies |
K-13 Recommended | Any automation cell with servo drives, VFDs, or multiple switch-mode power supplies — the default for modern automation |
Harmonic Sources | Servo drives, VFDs, switch-mode power supplies (PLCs, HMIs, sensors), DC bus rectifiers, robotic controllers |
Neutral Sizing | Double-sized neutral standard with K-13 — triplen harmonics are significant in automation control circuits |
Ground Noise | Isolation transformers break ground loops between drive systems and control networks — critical for fieldbus reliability |
Any automation cell with servo drives or VFDs should default to K-13 rated isolation transformers. Standard transformers will overheat and shorten service life significantly in these applications.
Ambient Temperature | 40°C standard — verify for enclosed machine cabinets where heat buildup may exceed this |
Coolant & Mist Exposure | CNC and machining environments — NEMA 12 or encapsulated units required |
Wash-down | Food, beverage, and pharmaceutical automation — encapsulated or NEMA 4/4X rated |
Vibration | Specify vibration isolation pads for transformers near presses, stamping, or high-vibration automation |
EMI Sensitivity | Isolation transformers reduce common-mode noise — important for high-resolution encoder and analog signal circuits |
Altitude | Derate above 1,000m — relevant for Alberta and BC interior automation facilities |
Frequently Asked Questions — Automation
What transformer do I need inside a PLC control panel?
The standard solution is a control transformer — typically 100 VA to 1,000 VA — providing isolated 120V AC power for the PLC processor, I/O cards, HMI, and safety relay modules. Control transformers are machine-tool rated with high short-circuit withstand current, which protects the transformer and downstream devices during fault conditions. The isolation from the main supply prevents voltage transients and ground noise on the main drive circuit from reaching sensitive PLC inputs and communications. Size the control transformer at 125% of the total VA draw of all connected control devices.
Do I need an isolation transformer for a robotic cell?
For most robotic cells, an isolation transformer feeding the cell is strongly recommended — and in many cases required by the robot manufacturer. Robotic controllers use high-frequency switch-mode power supplies that generate harmonic currents, and their encoder and fieldbus circuits are sensitive to ground noise. An isolation transformer at the cell input eliminates ground loops between the robot controller and the plant distribution, and a K-13 rated unit handles the harmonic load from multiple servo drives. For cells with 2 or more robots, size the isolation transformer at the sum of all robot and peripheral kVA ratings times 1.25.
How do I connect a European CNC machine (400V, CE-marked) to a Canadian 600V supply?
European machinery is rated for 400V, 3-phase, 50/60 Hz — which requires a step-down transformer from the Canadian 600V supply. An autotransformer with a 600V primary and 400V secondary is the most economical solution when galvanic isolation is not required. If the machine has a built-in control transformer or sensitive electronics, or if the machine builder’s documentation requires isolation, specify an isolation transformer instead. Always size at 125% of the machine nameplate kVA. For 230V single-phase loads within the machine (CE lighting, control devices), the machine’s internal transformer typically handles this from the 400V bus — confirm with the machine documentation.
Why does my PLC keep faulting and what does my transformer have to do with it?
Unexplained PLC faults, communications errors, and analog I/O drift are frequently caused by power quality issues — specifically ground noise and voltage transients on the control power circuit. If the PLC shares a power source with drive circuits (VFDs, servo amplifiers), inductive switching transients and harmonic distortion couple into the control power and cause these issues. The solution is a dedicated control transformer providing isolated control power — completely separate from the drive power circuit. This is the single most effective improvement for eliminating nuisance faults in automated systems. If the problem persists, an isolation transformer with electrostatic shielding may be required for particularly sensitive control systems.
What K-factor rating do I need for a machine with 4 servo drives?
A machine with 4 servo drives should be fed from a K-13 rated isolation transformer as a minimum. Servo drives are non-linear loads that generate significant 5th, 7th, 11th, and 13th harmonic currents. A standard K-1 transformer feeding this load will overheat — especially during high-duty cycles — reducing insulation life and eventually failing. K-13 is the widely accepted standard for automation and machine tool applications with multiple drives. For very large machine cells with 8 or more high-power servo axes, K-20 may be warranted — consult our technical team with the drive specifications.
Can I use one transformer to power both the drive circuits and control circuits in a machine?
Technically possible, but not best practice for automation systems. Sharing a transformer between drive power and control power allows noise and transients from the drive circuit to reach sensitive PLC and safety circuits. The recommended approach is two transformers: one isolation transformer (K-13 rated) for the main drive bus, and a separate smaller control transformer for the 120V control circuit. This is standard practice in professional machine design and eliminates the most common source of nuisance faults in automated equipment. The cost of a small control transformer is negligible compared to the cost of diagnosing and correcting control power interference issues after commissioning.
Do you supply transformers for OEM machine builders?
Yes — Transformer Source is a preferred supplier for OEM machine builders and systems integrators across Canada and the US. We offer volume pricing, consistent availability, CSA/UL certification documentation, and technical support for transformer selection. Our control transformers are machine-tool rated and available in all standard VA sizes for panel integration. Isolation and autotransformers are stocked in common machine kVA ranges for fast delivery. Contact us to discuss account pricing and availability for recurring machine builds.
What is the lead time for automation transformers?
Control transformers and small isolation transformers in standard VA/kVA ratings are stocked and typically ship within 1–3 business days. Larger isolation transformers (above 75 kVA), K-13 rated units in non-standard sizes, encapsulated units, and custom voltage configurations have lead times of 4–12 weeks. For OEM machine builders with regular build schedules, we recommend setting up a stocking arrangement to ensure availability. Contact us with your build schedule and transformer requirements.
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Ready to Specify Your Automation Transformer?
From single control transformers inside a machine panel to full isolation transformers feeding production cells — our technical team works with machine builders, systems integrators, and automation engineers to get the specification right the first time.
Have this information ready:
- Application type (control panel, machine cell, imported equipment, production line)
- Required VA or kVA and control voltage (120V, 24V, or other)
- Primary voltage (600V, 480V, 208V)
- Number and type of drive loads (VFDs, servo drives, switch-mode supplies)
- Installation environment (inside enclosure, plant floor, wash-down, outdoor)
- Certification requirements (CSA, UL, CE) and any machine-tool rating needs