POWISER VOLIX 3 ULTRA 12K — 12kW Portable Backup, on Casters
Ships freight — what to expect
Pre-order. POWISER's next U.S. stock of the ULTRA 12K is due at the end of December 2026. Orders placed now are expected to ship in January 2027.
Description
Availability: POWISER's next U.S. stock of the ULTRA 12K is due at its U.S. warehouse at the end of December 2026. Orders placed now are expected to ship in January 2027.
Whole-home backup power that rolls where you need it: a 12kW split-phase system on casters, with true UPS switching, dual solar inputs and no permanent wall installation to commit to.
Why it works in a serious garage
- 12kW / 12,000VA split-phase, 18,000VA peak. Real 120/240V output means the whole shop — compressor, welder, Level 2 charger, well pump — not just the 120V circuits a portable unit covers.
- True UPS, not just backup. 10 ms transfer time, so computers, networking gear and diagnostic equipment ride through an outage without rebooting.
- Portable, with no install. On casters and plug-connected rather than hardwired into your panel. If you move, it moves. That is the whole argument for this over a wall-mounted system.
- Outlets that match real equipment. Three 20A 120V outlets, a 30A 120V outlet and a 30A 120V/240V outlet — so RV service, welders and 240V tools plug in directly, without an adapter or a subpanel.
- Dual solar inputs, high and low voltage. Two high-voltage MPPT channels take a roof array up to 10,000W, and a separate 1,300W low-voltage input at 12–60Vdc takes 12V or 24V panels directly — useful for a camper, trailer or existing 12V setup without a second controller.
Specifications
| Rated output power | 12,000W / 12,000VA |
| Maximum peak power | 18,000VA |
| Rated output voltage | Split-phase — 120Vac (L1/N, L2/N) / 240Vac (L1/L2) |
| Output frequency | 50Hz / 60Hz |
| Output waveform | Pure sine wave |
| UPS transfer time | 10 ms (typical) |
| AC outlets | 3× 20A 120V, 1× 30A 120V, 1× 30A 120V/240V |
| DC output | 2× USB-A 18W QC3.0, 2× USB-C 100W PD, overcurrent protected |
| Battery type | Lithium iron phosphate (LiFePO₄) |
| Battery capacity | 10.24kWh (51.2V, 200Ah). Not expandable: external battery packs fit the H12 PRO only |
| Rated battery voltage | 51.2Vdc (range 40–58.6Vdc) |
| Grid / generator charging current | 160A |
| Maximum hybrid charging current | 200A |
| High-voltage PV input | 2 MPPT channels — 10,000W max (PV1 / PV2), 32A / 32A, 500Vdc max open-circuit |
| MPPT operating voltage range | 90–485Vdc |
| Low-voltage PV input | 1,300W max, 22A / 22A, 12–60Vdc operating, 60Vdc max open-circuit |
| MPPT tracking efficiency | 99.9% |
| Battery inverting efficiency | >92% |
| Grid / generator input | 120Vac (L1/N, L2/N) / 240Vac (L1/L2), 85–140Vac, 50/60Hz |
| Bypass overcurrent | 60A / 60A (L1, L2) |
| Parallel capability | Up to 6 units: 72kW output, about 60kWh storage |
| Certifications | UL 9540, UL 9540A, UL 1741, UL 1973 and FCC certification in progress. POWISER expects to complete them by the end of December 2026. Not yet listed. Off-grid and plugged-load use for now. |
| Protection rating | IP20 — indoor use only |
| Ambient temperature | Discharging: 5°F to 131°F (−15°C to 55°C), derated above 113°F (45°C). Charging: 32°F to 131°F (0°C to 55°C) |
| Cooling | Forced air |
| Noise | <60dB |
| Communication | CAN, parallel communication port, CT port, dry contact port, Wi-Fi monitoring through the POWISER app (App Store and Google Play release expected at the end of October 2026) |
| Dimensions (L×W×H) | 19.6 × 29.8 × 35.2 in (498 × 758 × 894 mm) |
| Weight | 309 lb (140 kg) |
| Warranty | 10 years, home energy storage |
Overload protection is staged: above 102% of rated load the unit alarms and shuts output down after 5 minutes, above 110% after 10 seconds, and above 125% after 5 seconds.
Protection and control
- Short-circuit, over-voltage, under-voltage, overload and reverse-feed protection
- Segmented and scheduled charge and discharge, with an energy-saving mode that cuts no-load consumption
- Four charging modes — solar only, grid priority, solar priority and hybrid
- Three system configurations supported — CT metering, UPS-style backup panel, or an external automatic transfer switch
What’s in the box
- POWISER VOLIX 3 ULTRA 12K on integrated casters
- User manual
Shipping & delivery
At 309 lb (140 kg) this ships by freight on a pallet, not parcel. Confirm your delivery access before ordering. Expect curbside delivery on a liftgate truck — the carrier will not bring it into the garage. The casters make it manageable once it is on the ground and on a flat surface, but getting it off the truck and over a threshold is a two-person job. Inspect the crate before signing.
Class 9 hazardous goods, ground or LTL freight only, no air, curbside delivery, someone must be present. Excluded from free shipping — freight on this unit is a flat $750 within the continental U.S., shown at checkout before you pay.
Frequently asked questions
Can it run 240V equipment?
Yes. Output is split-phase 120/240Vac and there is a dedicated 30A 120V/240V outlet on the unit, alongside a 30A 120V and three 20A 120V outlets. That is the main thing separating this from portable power stations, which are almost all 120V only.
Is it UL listed?
Not yet. POWISER is certifying the ULTRA 12K to UL 9540, UL 9540A, UL 1741 and UL 1973, along with FCC, and expects to finish by the end of December 2026. Until the certificates are issued, treat this as an off-grid and plugged-loads unit rather than a grid-tied installation, and check what your local authority requires before feeding household circuits. We will publish certificate numbers here as soon as POWISER supplies them.
Does it need an electrician?
Not in the way a hardwired system does — it is a portable unit on casters rather than something bonded into your service panel. If you want it feeding household circuits through a transfer switch, that connection does need a licensed electrician and requirements vary by jurisdiction. Note it is IP20 rated: indoor use only, not a carport or an exposed wall.
How much solar can I connect?
Two high-voltage MPPT channels take up to 10,000W combined at 32A per channel, with a 500Vdc open-circuit ceiling. Separately, a 1,300W low-voltage input accepts 12–60Vdc panels directly. The high-voltage channels track between 90 and 485Vdc. Size each string so its open-circuit voltage stays under 500Vdc with margin for cold weather, when Voc rises.
How is this different from the H12 PRO?
Same 12kW split-phase output and the same 10 ms transfer. The H12 PRO mounts to a wall and hardwires into your panel; the ULTRA 12K rolls on casters and plugs in. The H12 PRO takes up to two 10kWh expansion packs, while the ULTRA 12K's 10.24kWh battery is not expandable.
Can I add more later?
Up to six units run in parallel for 72kW of output and about 60kWh of storage. A single unit's battery is not expandable.
Build out the rest of the garage
- Autel AC Elite Home 50A 12kW EV Charger — the Level 2 charger this system is sized to support.
- ALLPOWERS SF-200 200W Flexible Solar Panel — low-profile panels for the high-voltage array input.
Certifications
-
POWISER VOLIX 3 ULTRA 12K — UL and FCC certification pending Pending
- Issued by
- Pending. POWISER expects certification by the end of December 2026
- Model
- VOLIX 3 ULTRA 12K
- Standards
-
- UL 9540 — PENDING, not yet listed
- UL 9540A — PENDING, not yet listed
- UL 1741 — PENDING, not yet listed
- UL 1973 — PENDING, not yet listed
- FCC — PENDING
Each record is taken from the certificate itself or the issuing body’s register. A radio or EMC authorization is not a product-safety listing — every record states its own scope.
Shipping & returns
Returns follow the stated return window — see returns & exchanges. Freight returns are arranged by our team.
Lithium battery shipments travel by ground only, never air, and can carry destination restrictions. Feeding household circuits through a transfer switch needs a licensed electrician and, in most places, a permit and inspection.
Who it is for
For backup power that moves when you do
The ULTRA 12K is the caster-mounted version of POWISER's 12kW split-phase platform: real 120/240V output from a unit you roll into place rather than hardwire. Plug equipment into its five AC outlets from day one. Feeding household circuits through a panel or transfer switch waits on UL certification, which is still pending. If you want a permanent wall installation with storage in the enclosure, its sibling is the VOLIX 3 H12 PRO.
- CONTINUOUS SPLIT-PHASE OUTPUT
- 12kW
- PEAK SURGE HEADROOM
- 18,000VA
- GRID-TO-BATTERY TRANSFER
- 10 ms
- MAX SOLAR INPUT, BOTH INPUTS
- 11,300W
What sets the ULTRA 12K apart
-
Real 240V circuits
Split-phase output and a dedicated 30A 120/240V outlet run a welder, RV service or 240V tools without an adapter or subpanel
-
Rolls, does not install
Locking casters and a removable rolling base: plug-connected rather than hardwired, so it moves when you do
-
Solar at two voltages
Two high-voltage MPPT channels to 10,000W, plus a separate 1,300W input that takes 12V or 24V panels directly
-
Parallels to 72kW
Six units run in parallel for 72kW of output and about 60kWh of storage
Built to move, sized for the house
Split-phase output on casters, with UPS switching and two solar inputs
-
Switches before your electronics notice
Transfer to battery is 10 ms typical, fast enough that computers, networking gear and diagnostic equipment ride through an outage without rebooting. The unit takes grid, generator and solar input, and can be set to solar only, grid priority, solar priority or hybrid charging.
10 ms typical transfer time
-
Outlets that match real equipment
Three 20A 120V outlets, a 30A 120V outlet and a 30A 120V/240V outlet, all pure sine wave, plus two 100W USB-C and two 18W USB-A ports for bench electronics. A touchscreen shows what the unit is doing.
5 AC outlets, 12,000W continuous
-
Built to move between sites
Locking casters roll it from the garage to an RV, a cabin or a job site and hold it in place once it is set up. The rolling base is removable for transport. It is rated IP20, so every location has to be indoors.
Locking casters, removable rolling base
-
Scales up as your needs grow
Run up to six units in parallel for 72kW of output and about 60kWh of storage. Feeding household circuits waits on UL certification, which POWISER expects to complete by the end of December 2026.
Up to 6 units in parallel, 72kW
How it compares
Published figures for the largest backup systems we carry
| Feature | ULTRA 12K | H12 PRO | Explorer 5000 Plus |
|---|---|---|---|
| Installation | Caster-mounted, plug-connected | Wall-mounted, hardwired | Portable, on wheels |
| Continuous output | 12,000W split-phase | 12,000W split-phase | 7,200W |
| Peak output | 18,000VA | 18,000VA | 14,400W |
| Transfer time | 10 ms typical | 10 ms typical | 0 ms online / 20 ms backup |
| Max solar input | 10,000W + 1,300W low-voltage | 10,000W | 4,000W high-PV |
| Parallel capability | Up to 6 units, 72kW | Up to 6 units, 72kW | Two stations, 14,400W |
| Battery voltage | 51.2Vdc | 51.2Vdc | Not published |
| Weight | 309 lb (140 kg) | 309 lb (140 kg) | 134.5 lb (61 kg) |
Full specifications
Every published figure for the VOLIX 3 ULTRA 12K
- Rated output power
- 12,000W / 12,000VA
- Maximum peak power
- 18,000VA
- Rated output voltage
- Split-phase: 120Vac (L1/N, L2/N) / 240Vac (L1/L2)
- Output frequency
- 50Hz / 60Hz
- Output waveform
- Pure sine wave
- UPS transfer time
- 10 ms (typical)
- AC outlets
- 3× 20A 120V, 1× 30A 120V, 1× 30A 120V/240V
- DC outputs
- 2× USB-A 18W QC3.0, 2× USB-C 100W PD, overcurrent protected
- Battery type
- Lithium iron phosphate (LiFePO₄)
- Battery capacity
- 10.24kWh (51.2V, 200Ah). Not expandable: external battery packs fit the H12 PRO only
- Rated battery voltage
- 51.2Vdc (range 40–58.6Vdc)
- Grid / generator charging current
- 160A
- Maximum hybrid charging current
- 200A
- High-voltage PV input
- 2 MPPT channels, 10,000W max (PV1 / PV2), 32A / 32A, 500Vdc max open-circuit
- MPPT operating voltage window
- 90–485Vdc
- Low-voltage PV input
- 1,300W max, 22A / 22A, 12–60Vdc operating, 60Vdc max open-circuit
- MPPT tracking efficiency
- 99.9%
- Battery inverting efficiency
- >92%
- Grid / generator input
- 120Vac (L1/N, L2/N) / 240Vac (L1/L2), 85–140Vac, 50/60Hz
- Bypass overcurrent
- 60A / 60A (L1, L2)
- Charging modes
- Solar only, grid priority, solar priority, hybrid
- System configurations
- Plugged loads; UPS-style backup panel; CT metering or external automatic transfer switch (the last two once UL certification is issued)
- Parallel capability
- Up to 6 units: 72kW output, about 60kWh storage
- Certifications
- UL 9540, UL 9540A, UL 1741, UL 1973 and FCC certification in progress. POWISER expects to complete them by the end of December 2026. Not yet listed
- Protection rating
- IP20, indoor use only
- Ambient temperature
- Discharging: 5°F to 131°F (−15°C to 55°C), derated above 113°F (45°C). Charging: 32°F to 131°F (0°C to 55°C)
- Cooling
- Forced air
- Noise
- <60dB
- Communication
- CAN, parallel communication port, CT port, dry contact port, Wi-Fi monitoring through the POWISER app (App Store and Google Play release expected at the end of October 2026)
- Dimensions (L×W×H)
- 19.6 × 29.8 × 35.2 in (498 × 758 × 894 mm)
- Weight
- 309 lb (140 kg)
- Mobility
- Locking casters, removable rolling base
- Warranty
- 10 years, home energy storage
Overload protection is staged: above 102% of rated load the unit alarms and shuts output down after 5 minutes, above 110% after 10 seconds, and above 125% after 5 seconds.
Build out the rest of the garage
Plain answers
Certification, solar sizing and moving it
Is it UL listed?
Not yet. POWISER is certifying the ULTRA 12K to UL 9540, UL 9540A, UL 1741 and UL 1973, along with FCC, and expects to finish by the end of December 2026. Until the certificates are issued, treat this as an off-grid and plugged-loads unit rather than a grid-tied installation, and check what your local authority requires before feeding household circuits. We will publish certificate numbers here as soon as POWISER supplies them.
Can it run 240V equipment?
Yes. Output is split-phase 120/240Vac, with a dedicated 30A 120V/240V outlet alongside a 30A 120V and three 20A 120V outlets. That is the main thing separating it from portable power stations, which are almost all 120V only.
Does it need an electrician?
Not for plugged loads: roll it in and plug equipment into its outlets. Feeding household circuits through a backup panel or a transfer switch does need a licensed electrician, requirements vary by jurisdiction, and that option waits on UL certification. It is rated IP20, so it must stay indoors.
How much solar can I connect?
Two high-voltage MPPT channels take up to 10,000W combined at 32A per channel, with a 500Vdc open-circuit ceiling. A separate 1,300W input accepts 12–60Vdc panels directly. The high-voltage channels track between 90 and 485Vdc. Size each string so its open-circuit voltage stays under 500Vdc with margin for cold weather, when Voc rises.
How is it different from the H12 PRO?
Same 12kW split-phase output and the same 10 ms transfer. The H12 PRO mounts to a wall and hardwires into your panel; the ULTRA 12K rolls on casters and plugs in. The H12 PRO takes up to two 10kWh expansion packs, while the ULTRA 12K's 10.24kWh battery is not expandable.
Can I add more later?
Up to six units run in parallel for 72kW of output and about 60kWh of storage. A single unit's battery is not expandable.
Is it easy to move between locations?
It rolls on locking casters from the garage to an RV, a cabin or a job site and locks in place once set up. At 309 lb, getting it over a threshold is a two-person job, and every location has to be indoors.
Before you order
Availability. POWISER's next U.S. stock of the ULTRA 12K is due at its U.S. warehouse at the end of December 2026. Orders placed now are expected to ship in January 2027.
At 309 lb (140 kg) the ULTRA 12K ships by freight on a pallet, not parcel: Class 9 hazardous goods, ground or LTL freight only, no air. Freight is a flat $750 within the continental U.S., shown at checkout before you pay. Expect curbside delivery on a liftgate truck; the carrier will not bring it into the garage. Someone must be present to receive it, and the crate should be inspected before signing.
For plugged loads there is nothing to install. Feeding household circuits through a backup panel or an external transfer switch requires a licensed electrician and waits on UL certification. The IP20 rating means indoor use only, never a carport or an exposed wall.
Warranty: 10 years, home energy storage. Returns are handled under our return and refund policy. Freight items must be inspected at delivery and any transit damage noted on the carrier paperwork before signing.
