A spare inverter can save a distributor’s customer from a long shutdown. But a box that has been sealed for years is not automatically ready to connect to a pump. The question is not simply whether it is “new.” For spare pump VFD storage, you need to know how long the unit has been unpowered, where it was kept, and what its own manufacturer requires before first energizing it.
The practical answer: inspect the unit and its records before it goes to site. If the storage period is long or unknown, do not invent a capacitor re-forming procedure. Ask the supplier for the exact model’s written instructions and use qualified personnel for any electrical preparation.
Spare pump VFD storage start with the box, not the pump panel
Read the production date or serial-number information and note the date it entered your stock. Those can be different. Check whether the carton was stored in a dry, clean area within the manufacturer’s temperature and humidity limits. Look for condensation marks, corrosion, damaged packaging, insect contamination and signs that a supposedly spare unit was previously energized or repaired.
Keep a simple record: model, voltage class, output rating, serial number, manufacturing date if available, arrival date, storage location and inspection date. If you cannot establish the period without power, mark it as unknown, not “less than a year.” That one honest entry changes the next decision.
Why long storage can affect a drive
The DC-link capacitors inside a drive can need special treatment after an extended unpowered period. Different manufacturers and drive families set different time and temperature conditions. Schneider Electric’s Process Drive storage guidance links the action to both storage duration and temperature. A separate Schneider article for older Altivar models describes a different procedure. The fact that two official instructions differ is the point: neither is a safe universal recipe for a BEDFORD inverter.
A distributor should not print another brand’s voltage steps on a BEDFORD work order. Ask BEDFORD for the model-specific instruction and whether the unit should be inspected or conditioned by an authorized service team before use. Do not let a customer improvise a live-voltage test at a pump site.
A three-way decision for the stockroom
- Traceable, clean and within the stated storage interval: complete the normal pre-installation inspection and follow the model manual.
- Traceable but beyond that interval: hold the unit for a manufacturer-approved preparation procedure. Record who performed it and when.
- Unknown age or visible damage: quarantine the unit. Do not sell it as ready-to-install stock until the supplier has assessed it.
This is a stocking decision, not just an electrical one. A unit that cannot be supported with records may cause a difficult dispute even if the eventual failure has another cause.
After the spare is cleared, it still has to match the pump
Storage clearance does not prove application fit. Check the motor’s rated voltage and current, the supply phase and voltage, the pressure sensor or level-control scheme, and the required start/stop logic. A spare from another project may have the right kW label and the wrong input or control arrangement. The W713B page is a useful reference for constant-pressure pump functions, while our pump inverter sizing guide covers motor matching. Neither replaces an exact review of the unit on the shelf.
Before dispatch, give the installer a copy of the storage check and a blank commissioning record. If the spare works well, those two pages will make the next replacement faster too. If it does not, the team will know what was verified before it reached the site.
Before dispatch, give the installer a copy of the storage check and a blank commissioning record. If the spare works well, those two pages will make the next replacement faster too. If it does not, the team will know what was verified before it reached the site.