Powervolt Group GP Enclosed Series: Complete Guide
July 2, 2026
| 📖 Part of the Powervolt Group Industrial Control Transformers knowledge hubThis article covers the GP Enclosed Series in depth. For a complete overview of all three Powervolt control transformer series, VA sizing methodology, and certifications, see the full pillar guide. |
← Back to: Industrial Control Transformers — Complete Guide
The GP Enclosed Control Transformers Series integrates a Powervolt Group control transformer into a NEMA 3R nonventilated weatherproof enclosure – for installations where the transformer must be mounted outside an existing control panel, outdoors, or in an environment exposed to rain, dust, or other contaminants.
The Enclosed Series spans 6 VA ratings – 250, 500, 750, 1000, 1500, and 2000 VA – each available across multiple voltage groups and frequency variants, for a total of 58 part numbers. All units carry UL Listed Class 5085-2 (File E47299), are CE marked, RoHS, and REACH compliant, and backed by Powervolt Group’s 10-year warranty. Manufactured and 100% tested in Addison, Illinois, USA.
| Browse & Check Price — All 58 Enclosed ModelsEvery GP Enclosed part number is stocked at Powervolt Group’s Addison, Illinois facility. Check live pricing, datasheets, and availability.→ Browse GP Enclosed Series on powervoltgroup.com → |
Powervolt Group: 1-888-797-8658 (Toll Free) | (630) 628-9999 | [email protected]
What Defines the GP Enclosed Series
Open-frame transformers – like GP Standard and GP Econoline – rely on the host control panel for environmental protection. The GP Enclosed Series builds that protection directly into the unit, making it suitable for mounting outside a panel altogether.
- Power rating: 250 VA to 2000 VA (6 steps)
- Primary voltage: 208–600 V across 5 voltage groups (D: 600V, M: 240/480V, V: 208V, CM: 480V, EG: 380/400/416V)
- Secondary voltage: 120/240 V (fixed across all models)
- Frequency: 50/60 Hz or 60 Hz only, depending on model variant
- Enclosure: NEMA 3R nonventilated weatherproof enclosure – protects against rain, sleet, and external moisture
- Knockouts: provided on back and bottom of enclosure for conduit entry
- Core: high-grade silicon steel core
- Mounting: mounting holes on side panel for easy access and installation
- Wiring compartment: includes a ground stud for code-compliant grounding
- Certifications: UL Listed Class 5085-2, UL File E47299, CE marked, RoHS, REACH
- Warranty: 10 years – Powervolt Group, Addison, Illinois, USA
- Part numbering: GP[VA]-[Group][Frequency]EN – for example GP0250-D50EN (600 V, 50/60 Hz) or GP0250-D60EN (600 V, 60 Hz only)
Need an open-frame unit instead — for mounting inside an existing panel? See the GP Standard A00 Series Guide or the GP Econoline Series Guide. For the full three-series comparison, see the pillar guide.
| 💡 When to choose GP Enclosed over open-frameSpecify the GP Enclosed Series whenever the transformer will be mounted outside a NEMA-rated control panel — on an outdoor structure, a machine frame without a sealed enclosure, or in a washdown or dusty plant area. If the unit will sit inside an existing panel, GP Standard or GP Econoline open-frame units are more cost-effective. |
All 58 Enclosed Models at a Glance
Click any part number to go directly to its live product page on powervoltgroup.com. All carry UL File E47299.
250 VA Models – Light Outdoor / External Control
Best for small outdoor control panels, light annunciator circuits, and external-mount applications below 500 VA.
| Part No. | Primary Voltage | Frequency | Application |
|---|---|---|---|
| GP0250-D50EN | 600V | 50/60Hz | Highest-voltage outdoor mounting |
| GP0250-D60EN | 600V | 60Hz | Highest-voltage outdoor mounting, 60Hz only |
| GP0250-M50EN | 240/480V | 50/60Hz | Standard NA dual-voltage outdoor mounting |
| GP0250-M60EN | 240/480V | 60Hz | Standard NA dual-voltage outdoor mounting, 60Hz only |
| GP0250-CM50EN | 480V | 50/60Hz | 480V single-voltage outdoor mounting |
| GP0250-CM60EN | 480V | 60Hz | 480V single-voltage outdoor mounting, 60Hz only |
| GP0250-EG50EN | 380/400/416V | 50/60Hz | International voltage outdoor mounting |
| GP0250-EG60EN | 380/400/416V | 60Hz | International voltage outdoor mounting, 60Hz only |
500 VA Models – Mid-Size Outdoor Control
Suited to outdoor motor starters, weatherproof junction panels, and moderate automation loads.
| Part No. | Primary Voltage | Frequency | Application |
|---|---|---|---|
| GP0500-D50EN | 600V | 50/60Hz | Highest-voltage outdoor mounting |
| GP0500-D60EN | 600V | 60Hz | Highest-voltage outdoor mounting, 60Hz only |
| GP0500-M50EN | 240/480V | 50/60Hz | Standard NA dual-voltage outdoor mounting |
| GP0500-M60EN | 240/480V | 60Hz | Standard NA dual-voltage outdoor mounting, 60Hz only |
| GP0500-V60EN | 208V | 60Hz | 208V outdoor mounting, 60Hz only |
| GP0500-CM50EN | 480V | 50/60Hz | 480V single-voltage outdoor mounting |
| GP0500-CM60EN | 480V | 60Hz | 480V single-voltage outdoor mounting, 60Hz only |
| GP0500-EG50EN | 380/400/416V | 50/60Hz | International voltage outdoor mounting |
| GP0500-EG60EN | 380/400/416V | 60Hz | International voltage outdoor mounting, 60Hz only |
750 VA Models – Heavier Outdoor Automation
For larger outdoor control circuits, multi-relay panels, and washdown-adjacent (non-hose-down) environments.
| Part No. | Primary Voltage | Frequency | Application |
|---|---|---|---|
| GP0750-D50EN | 600V | 50/60Hz | Highest-voltage outdoor mounting |
| GP0750-D60EN | 600V | 60Hz | Highest-voltage outdoor mounting, 60Hz only |
| GP0750-M50EN | 240/480V | 50/60Hz | Standard NA dual-voltage outdoor mounting |
| GP0750-M60EN | 240/480V | 60Hz | Standard NA dual-voltage outdoor mounting, 60Hz only |
| GP0750-V60EN | 208V | 60Hz | 208V outdoor mounting, 60Hz only |
| GP0750-CM50EN | 480V | 50/60Hz | 480V single-voltage outdoor mounting |
| GP0750-CM60EN | 480V | 60Hz | 480V single-voltage outdoor mounting, 60Hz only |
| GP0750-EG50EN | 380/400/416V | 50/60Hz | International voltage outdoor mounting |
| GP0750-EG60EN | 380/400/416V | 60Hz | International voltage outdoor mounting, 60Hz only |
1000 VA Models – High-Load External Panels
For SCADA outstations, larger PLC-driven outdoor panels, and remote equipment control rooms.
| Part No. | Primary Voltage | Frequency | Application |
|---|---|---|---|
| GP1000-D50EN | 600V | 50/60Hz | Highest-voltage outdoor mounting |
| GP1000-D60EN | 600V | 60Hz | Highest-voltage outdoor mounting, 60Hz only |
| GP1000-M50EN | 240/480V | 50/60Hz | Standard NA dual-voltage outdoor mounting |
| GP1000-M60EN | 240/480V | 60Hz | Standard NA dual-voltage outdoor mounting, 60Hz only |
| GP1000-V60EN | 208V | 60Hz | 208V outdoor mounting, 60Hz only |
| GP1000-CM50EN | 480V | 50/60Hz | 480V single-voltage outdoor mounting |
| GP1000-CM60EN | 480V | 60Hz | 480V single-voltage outdoor mounting, 60Hz only |
| GP1000-EG50EN | 380/400/416V | 50/60Hz | International voltage outdoor mounting |
| GP1000-EG60EN | 380/400/416V | 60Hz | International voltage outdoor mounting, 60Hz only |
1500 VA Models – Heavy-Duty Outdoor Automation
For large outdoor MCC-style enclosures, multi-zone irrigation or water treatment control, and heavy automation infrastructure.
| Part No. | Primary Voltage | Frequency | Application |
|---|---|---|---|
| GP1500-D50EN | 600V | 50/60Hz | Highest-voltage outdoor mounting |
| GP1500-D60EN | 600V | 60Hz | Highest-voltage outdoor mounting, 60Hz only |
| GP1500-M50EN | 240/480V | 50/60Hz | Standard NA dual-voltage outdoor mounting |
| GP1500-M60EN | 240/480V | 60Hz | Standard NA dual-voltage outdoor mounting, 60Hz only |
| GP1500-CM50EN | 480V | 50/60Hz | 480V single-voltage outdoor mounting |
| GP1500-CM60EN | 480V | 60Hz | 480V single-voltage outdoor mounting, 60Hz only |
| GP1500-EG50EN | 380/400/416V | 50/60Hz | International voltage outdoor mounting |
| GP1500-EG60EN | 380/400/416V | 60Hz | International voltage outdoor mounting, 60Hz only |
2000 VA Models – Maximum-Capacity Outdoor Infrastructure
For the highest-load external control applications – central plant infrastructure, large outdoor automation hubs, and remote substations.
| Part No. | Primary Voltage | Frequency | Application |
|---|---|---|---|
| GP2000-D50EN | 600V | 50/60Hz | Highest-voltage outdoor mounting |
| GP2000-D60EN | 600V | 60Hz | Highest-voltage outdoor mounting, 60Hz only |
| GP2000-M50EN | 240/480V | 50/60Hz | Standard NA dual-voltage outdoor mounting |
| GP2000-M60EN | 240/480V | 60Hz | Standard NA dual-voltage outdoor mounting, 60Hz only |
| GP2000-V60EN | 208V | 60Hz | 208V outdoor mounting, 60Hz only |
| GP2000-CM50EN | 480V | 50/60Hz | 480V single-voltage outdoor mounting |
| GP2000-CM60EN | 480V | 60Hz | 480V single-voltage outdoor mounting, 60Hz only |
Shared Specifications – GP Enclosed Series
| Specification | Value |
|---|---|
| Power rating | 250 VA to 2000 VA |
| Primary voltage | 208–600 V across |
| Secondary voltage | 120/240 V (fixed) |
| Frequency | 50/60 Hz or 60 Hz only — depends on model variant |
| Enclosure rating | NEMA 3R — nonventilated, weatherproof |
| Knockouts | Provided on back and bottom for conduit entry |
| Core | High-grade silicon steel |
| Mounting | Mounting holes on side panel |
| Wiring compartment | Includes ground stud |
| Certifications | UL Listed Class 5085-2 (File E47299), CE marked, RoHS, REACH |
| Warranty | 10 years — Powervolt Group Inc., Addison, Illinois, USA |
| Made in | USA — 100% manufactured and tested in Addison, Illinois |
Choosing the Right Enclosed Model
Step 1 – Confirm your primary voltage and frequency
GP Enclosed is organised by primary voltage group: 600 V (Group D), 240/480 V (Group M), 208 V (Group V, 60 Hz only), 480 V (Group CM), or 380/400/416 V (Group EG), or 120/240 V (Group PM). Confirm whether your supply requires a 50/60 Hz dual-rated unit or a 60 Hz-only variant.
Step 2 – Size to total connected and inrush VA
Use the same load-cataloguing and inrush-summation method described in Section 4 of the pillar guide. Sum sealed VA plus inrush VA of all simultaneously energising devices, then select the next standard Enclosed VA rating: 250, 500, 750, 1000, 1500, or 2000 VA.
Step 3 – Confirm enclosure suitability for your environment
NEMA 3R protects against falling rain, sleet, and external ice formation, and is suitable for outdoor mounting where the enclosure will not be submerged or subject to direct hose-down washdown. For washdown or corrosive environments requiring NEMA 4X, contact Powervolt Group’s custom design team.
| ⚠️ NEMA 3R is not a washdown ratingNEMA 3R protects against rain and external ice but is not rated for hose-directed water (NEMA 4) or corrosive washdown chemicals (NEMA 4X). If your installation involves direct washdown — common in food processing or pharmaceutical plants — contact Powervolt Group’s custom design team before specifying a standard Enclosed model. |
Enclosed Series Installation Notes
- Mount using the side-panel mounting holes – designed for easy access in outdoor or external installations
- Route conduit through the pre-provided knockouts on the back and bottom of the enclosure
- Use the integral ground stud in the wiring compartment to bond the enclosure and secondary neutral per NEC 250.186
- Verify the enclosure’s NEMA 3R rating is adequate for the installation location before mounting outdoors
- Install primary and secondary overcurrent protection per NEC Articles 430 and 725, as with any control transformer
For full grounding and wiring guidance applicable to all Powervolt control transformers, see Section 6 of the Industrial Control Transformers pillar guide.
Order the GP Enclosed Series from Powervolt Group
All 58 Enclosed part numbers are stocked at 300 W Factory Road, Addison, IL 60101 with 3-day standard shipment. OEM pricing contracts and volume discount programmes are available.
- Browse all GP Enclosed models – pricing, datasheets, stock status
- GP Standard A00 Series – for open-frame panel-mount applications
- GP Econoline Series – cost-optimised open-frame alternative
- Cross-Reference Tool – find Powervolt Group equivalents for any competitor part number
- Custom Design Form – non-standard enclosure rating or voltage requirements
| Request a Quote — Same-Day ResponseSubmit your Enclosed Series part number, quantity, and delivery requirement and Powervolt Group’s sales team will respond within one business day with OEM pricing and lead time.→ Request a Quote from Powervolt Group → |
Powervolt Group Inc. | 300 W Factory Rd, Addison, IL 60101 | 1-888-797-8658 | (630) 628-9999 | [email protected] | Mon–Fri 7:30 AM – 4:00 PM CT
GP Enclosed Series – FAQ
What does NEMA 3R protect against?
NEMA 3R enclosures protect against falling rain, sleet, and external ice formation, and provide protection against windblown dust. They are not rated for direct hose-down washdown (NEMA 4) or corrosion resistance (NEMA 4X).
Can the Enclosed Series replace an open-frame unit inside a panel?
Yes, but it is not cost-effective to do so — the enclosure adds cost and size with no benefit if the unit is already protected by a panel. For inside-panel applications, specify GP Standard or GP Econoline instead.
Does the Enclosed Series carry the same warranty as Standard and Econoline?
Yes – all three Powervolt Group control transformer series carry the same 10-year warranty and UL File E47299 listing.
Related Content
- Pillar guide: Industrial Control Transformers – Complete Guide | Powervolt Group
- GP Standard A00 Series: Full guide – 14 VA steps, 25–2000 VA, open-frame
- GP Econoline Series: Cost-optimised open-frame – 300, 750, 1500 VA
- Product catalogue: GP Enclosed Series – all 58 part numbers, pricing, and stock
- Cross-reference: Find Powervolt Group equivalents for any competitor part number