Impressed current, off the grid.
The PV DC Current Controller is our own solar-powered rectifier for cathodic protection. It puts a regulated DC current source on the asset itself — no utility service, no meter, no trench to a panel — and holds the structure at criterion on a solar module and a lithium battery.
- No utility service
- 12 V · 5 A to 24 V · 22 A
- LiFePO4 storage
- CI RMU factory option
The film · 1:01
The PV controller in one minute.
From the sun to the structure: the cabinet, the panel, what is behind it and what ships with every system.
Every side
Every side of the cabinet.
Stainless steel, NEMA 4X, 20 × 16 × 10 in, with the satellite and cellular antennas on the roof.
The problem
On most sites, the power is the expensive part.
Remote tanks and pipeline test stations rarely sit next to a service. Getting a rectifier energized the conventional way means a utility application, a trench, a meter and a standing charge — often the largest single line item in the project, and months of it before any current flows.
Nothing to apply for
The current source sits on the asset it protects. No utility application, no easement for a service run, no coordination with a third party before commissioning.
Nothing to meter
A conventional rectifier draws power for the life of the asset and bills for it monthly. A PV unit has no recurring energy cost at all.
One post, one crew
Module, controller and battery mount to a single concrete-filled galvanized post, or straight to the tank. Set, wire, commission — the same visit.
Collect
A south-facing monocrystalline module charges the battery through a 20 A solar charge controller.
Store
A 12 V lithium iron phosphate bank carries the system through night and overcast.
Regulate
The controller holds a set DC output — by voltage or by current — onto the anode ground bed.
Protect
Current returns through the electrolyte onto the structure and holds it at the −850 mV criterion.
Three sizes
Sized to the current the structure actually needs.
Output is set from the design calculation — surface area, coating condition and current density. We size the module and the battery to the duty, so the unit still delivers on a short winter day.
Water storage tanks and short pipe runs. 200 W module, 100 Ah battery.
Price on requestMedium to large water tanks and medium-scale underground pipe. 300 W module, 200 Ah battery.
$7,500Large tanks and extensive pipeline networks — where the ground bed needs real driving voltage.
Price on requestOutput limits are set in the controller as over-voltage and over-current protection, so a unit cannot be driven past its rating in the field.
Inside the cabinet
Everything a technician needs, on the door.
A stainless NEMA 4X enclosure with the meter, the isolators and the test points laid out so a routine check takes minutes and never needs the cabinet opened up.
- Digital output meter. Volts, amps and watts live, with V-SET and I-SET adjustment and over-voltage / over-current limits held in the controller.
- Instant-off switch. Interrupts the output for IR-free readings without touching the wiring.
- Three isolators. Solar, Main Power and RMU switch independently, so the array or the monitoring can be taken out without dropping protection.
- Fused throughout. Each of the three circuits carries its own fuse at the panel.
- Metering test points. Volts, Ref Cell, Structure and Shunt terminate on the door — structure-to-soil and instant-off readings without breaking into the wiring.
- Legible thresholds. The door carries the numbers that matter: if output falls below 0.50 V or 0.01 A, something has changed and we want the call.
- Stainless throughout. NEMA 4X rated, rated for −40 °F to 140 °F, and it still looks like this after a summer in Arizona.
Factory option
The CI RMU ships inside it.
Order the controller with our remote monitoring unit and it reports live volts and amps over cellular, satellite or WiFi, alarms you and us the moment it turns off, and takes a new output setting from the portal — no subscription.
Meet the CI RMU →
| Output | 12 V 5 A · 12 V 10 A · up to 24 V 22 A |
|---|---|
| Regulation | Constant voltage or constant current, set at the panel |
| Protection | Over-voltage and over-current limits; fused solar, main and RMU circuits |
| Charge controller | 20 A solar charge controller, 30 V max input, over-temperature protection |
| PV module | 200 W or 300 W monocrystalline, 24 V |
| Storage | 12 V 100 Ah or 200 Ah LiFePO4 with integral BMS |
| Enclosure | Stainless steel, NEMA 4X, 20 × 16 × 10 in, padlockable |
| Test points | Volts, reference cell, structure, shunt |
| Output wiring | #10 THHN pair in ¾″ liquid-tight; 18 ga 3C shielded for structure sense |
| Mounting | 3″ galvanized post set in concrete, or on the structure |
| Monitoring | CI RMU factory option: cellular, satellite and WiFi |
| Add-ons | Security lighting, security camera, annual maintenance inspection |
| Installation | Per NEC. Drawings stamped by a NACE-certified CP Specialist. |
Field record
In service on tanks and pipelines across California and Arizona.
Welded reservoirs, bolted tanks, municipal and campus water systems, and a new sewer force main — designed, built, installed and commissioned by us. Every one came with stamped drawings, a commission report and an ICCP operations and maintenance manual.
Every system ships with stamped design drawings, an installation and commission report, and an ICCP operations and maintenance manual.
Download the data sheet (PDF) Book a survey firstPV DC Current Controller · quote
Tell us the structure and we will size it.
Send the asset type, the dimensions, the coating condition and whether there is power at the site. We come back with the current requirement, the controller size, the module and battery, and a price — including the anode ground bed if you need the whole system.