Module and Inverter Delivery and Storage

Purpose

There is a short window, measured in minutes at the tailgate, in which damaged freight is the carrier's problem. After a clean signature it becomes the shop's problem, and the shop's options narrow to a concealed-damage claim that is far harder to win. This procedure holds that window open long enough to look.

It also produces the one record that makes a module warranty payable years later: the serial number, tied to a physical position on the roof and a date. A module that browns out in year nine is a warranty claim if you can name it and a customer-relations problem if you cannot. The manufacturer will not accept "the third one from the left."

Scope

Covers receiving, inspecting, staging and storing PV modules, inverters, optimizers and microinverters, racking, and packaged battery units, at the shop or delivered direct to a jobsite.

Does not cover commissioning or the functional tests that happen after equipment is installed. Does not cover the disposition of a module damaged during installation, which is an internal breakage record rather than a freight claim. Does not resolve the legal effect of a bill of lading or a claim denial; where a claim is contested, that is a question for the shop's own attorney or insurance agent, not for the receiving tech.

Roles and responsibilities

Procedure

1. Confirm the delivery before it leaves the terminal. Reconfirm the date, the address, whether the site has a forklift or needs a liftgate, and who will be physically present with authority to refuse. Acceptance: a named receiver, a confirmed unload method, and a delivery window under four hours. Wrong looks like a jobsite drop with nobody there, which produces a driver signature, a pallet on a lawn, and no inspection. Stop rule: no named receiver means the delivery is redirected to the shop rather than accepted blind.

2. Inspect the load before anything comes off the truck. Walk the trailer and photograph the load as it sits: banding intact or cut, pallets upright or leaning, shrink wrap torn, water staining on cartons, any pallet crushed by the one above it. Acceptance: photographs taken from inside or at the trailer door before the first pallet moves. Wrong is unloading first and inspecting after, which lets the carrier argue the damage happened on your ground. Hazard: do not enter a trailer whose load has shifted and do not stand under a suspended pallet; a leaning module pallet weighs more than it looks and comes down as a unit.

3. Count and inspect at the tailgate, then write on the receipt before you sign. Count pallets and cartons against the packing list, and on each pallet check the corners, the bottom cartons, and both long sides for punctures, crush and moisture. Note every finding on the delivery receipt in specific words - "pallet 2, tine puncture through the west side carton, module position 3" - and photograph the note itself alongside the damage. Acceptance: pallet count matches, and any exception is written in specific terms with the driver present. Wrong is signing clean, and nearly as wrong is writing "subject to inspection," which names no damage and is weak evidence later. Stop rule: visible damage means that pallet is refused or accepted-with-exception in writing, never accepted clean and sorted out later. For interstate motor carriage under a bill of lading, federal law requires the carrier's terms to allow at least nine months to file a written claim, at 49 U.S.C. 14706(e), but a contract carrier's terms and your own purchase agreement may differ, so the operative deadline is the one in the paperwork for this shipment.

4. Open a sample and apply the handling rules from the first module you touch. Open at least one carton per pallet and inspect glass for cracks, frames for deformation, backsheets for scuffs or punctures, junction boxes for lifted adhesive, and connectors for damage. Carry modules by the frame with two people, never by the junction box or the leads, and never stand or kneel on glass. Acceptance: the sampled modules are clean on all five points and the pallet's banding is left intact until the point of use. Wrong is a module carried one-handed by its junction box, which stresses the box adhesive and can start a moisture path years later. Hazard: the damage that matters most here is invisible - cell microcracks from a drop or a flexed frame do not show on the glass and only appear later as a hot spot or a low-performing module, so any module that has been dropped is set aside and marked rather than installed on the argument that it looks fine.

5. Capture serials before anything is staged. Scan or photograph every module serial, every inverter and optimizer serial, and every battery serial, and record them against the purchase order and the job they are allocated to. Acceptance: a serial count equal to the accepted unit count, with no manual transcription; a photographed label beats a typed number. Wrong is capturing serials at install only, which leaves anything stolen, damaged or returned before install with no identity at all. Stop rule: a unit whose label is unreadable does not get staged; it goes back to the supplier as a labeling defect, because an unlabeled module is unwarrantable from the day it arrives.

6. Stage and store modules by the manufacturer's rules, not by what fits. Store pallets on level ground or level racking, keep them banded, and do not exceed the stacking limit printed on the pallet or given in the module's installation manual. Keep cartons dry, since wet cardboard collapses and lets a pallet lean, and keep pallets out of traffic lanes where a forklift tine can reach them. Acceptance: every pallet level, banded, within its printed stack limit, and photographed in its storage position on the day it lands. Wrong looks like a third pallet stacked on a two-high limit because the bay was full. Hazard: a leaning or over-stacked pallet is the one that comes down on someone, so correct the stack the day you find it rather than working around it.

7. Store inverters and batteries indoors, within the manual's stated limits. Keep inverters and battery units in their cartons, indoors, dry, and inside the storage temperature range printed in each manual, and keep the original packaging until commissioning is signed off because most return authorizations require it. Store lithium battery units at the state of charge and temperature the manufacturer specifies for extended storage. Acceptance: storage temperature and humidity within the manual's range, cartons intact, batteries at the specified storage charge. Wrong is an inverter left in an unconditioned trailer through a cold night and opened warm the next morning, which condenses moisture inside an enclosure that is about to be energized. Hazard: a battery unit with any sign of impact, swelling, heat or fluid is not brought indoors and not stacked - it goes to an isolated outdoor location away from structures and vehicles and the manufacturer's emergency line is called, and where your AHJ has adopted NFPA 855 the fire code official's storage conditions bind the facility and reach the shop through the permit.

8. Release to the crew and reconcile what comes back. Issue units to a job by serial, and at close-out reconcile issued against installed against returned. Acceptance: every serial issued is accounted for as installed at a mapped position, returned to stock, or written off with a reason. Wrong is a truck that returns with three modules and no paperwork, which is how inventory drifts until a count says the shop owns units it cannot find. Stop rule: any unreconciled serial is investigated the same week, because a module that walked off a site is also a module the shop may later see in a warranty claim it cannot explain.

The record this produces

• Receiving record per delivery: carrier, pro number, date and time, pallet and carton counts, exceptions written on the receipt, photographs of the load, the damage, and the annotated receipt.
• Serial register: every serial received, with purchase order, job allocation, and eventual disposition (installed, returned, written off).
• Storage log: pallet positions, stack heights, indoor storage conditions for inverters and batteries.
• Module map at install: serial against physical position on the array, and the install date.

Purchasing files claims from the receiving record. Warranty claims years later run on the serial register and the module map together, which is the pairing that makes a claim payable rather than arguable. Insurance and any theft report run on the same serials.

A worked pass, including the step that failed

A residential job needing 78 modules, shipped as three pallets of 26, delivered to the shop.

Step 1: receiver named, forklift available, window confirmed. Step 2: the trailer is photographed at the door. Pallets 1 and 3 are upright with intact banding; pallet 2 is leaning slightly with the shrink wrap torn along one side.

Step 3 fails. Inspecting pallet 2 at the tailgate finds a forklift tine puncture through the side carton at the third module position, with the frame visibly bent behind it. The stop rule runs. The receiver writes on the delivery receipt "pallet 2 refused, tine puncture through west side carton at module position 3, frame deformed," photographs the damage and the annotated receipt with the driver present, and refuses the whole pallet rather than sorting good from bad on the dock. Pallets 1 and 3 are accepted clean, so 52 of 78 modules are on hand.

Step 4: one carton opened per accepted pallet, all five inspection points clean, banding left intact. Step 5: 52 serials scanned against the purchase order, no unreadable labels. Step 6: both pallets stored level and banded, one high against a two-high printed limit, photographed in position. Step 7: the inverter is stored indoors in its carton within the manual's stated range.

Step 8 reconciles forward rather than back, because the shortage now drives scheduling. The layout is six strings of 13 modules, and 52 modules build exactly four complete strings, so the crew lead re-sequences to install those four strings and the full racking on the original date, with the remaining 26 modules and two strings scheduled against the replacement pallet's confirmed delivery. Purchasing files the claim from the annotated receipt and photographs the same day.

Outcome: the damaged pallet is the carrier's, not the shop's, the crew still works its booked day, and the customer hears one revised completion date rather than discovering a half-finished array.

References

• 49 U.S.C. 14706 and 49 CFR Part 370, federal cargo claim rules for interstate motor carriage under a bill of lading; contract carriage and your own purchase terms may set different windows, and a contested claim is a question for your attorney or insurance agent.
• Module installation manual for handling, stacking limits and storage conditions; inverter and battery manuals for storage temperature range and extended-storage state of charge.
• NFPA 855, in the edition your authority having jurisdiction has adopted, which binds the facility and reaches the shop through the permit, for energy storage system storage and separation.
• See related: the roof condition assessment SOP and the energized DC array safety standard for what happens once these units leave storage.