Module Manufacturer Frame Sourcing: 12 Questions for Suppliers
Key Takeaway
Before a module OEM locks a GRPU or aluminum frame supplier, ask 12 questions and file the answers: drawing ownership, real-volume capacity and lead time, lot checks, test reports on that drawing, the retest rule, packing damage, and a named person for rejects. A unit price and a sample do not close the decision.
Table of Contents
The Meeting That Stops at Price
A frame-supplier question is a request for a fact you can attach to the purchase order: a name, a quantity, a revision, or a report number. Module makers often end the first meeting once the price per meter looks lower than the incumbent. The line then discovers that tooling sits at another plant, the quoted lead time was for samples, and a cracked corner has no owner.
Use the same twelve questions for a glass-fiber-reinforced polyurethane frame and for an aluminum frame. The material answer changes. The management questions do not. Weltrus manufactures GRPU frames for module OEMs and will answer this list in writing when the RFQ includes the drawing, the annual quantity, and the material. This page does not publish Weltrus capacity, lead time, or a customer list. Those figures belong on your RFQ reply, because they move with the profile.
Two documents sit beside the meeting. The field list that makes quotes comparable is in GRPU frame RFQ specs, MOQ, and lead time. The reports that must be in the folder are in the GRPU frame testing checklist. Ask the questions here. Put the numbers in those files.
Supply and Commercial Terms
1. Who owns the drawing, the tooling, and the corner design?
Record whether the profile drawing is yours, the supplier’s, or shared, and what happens to tools and corner keys if you stop buying. A complete answer names the drawing number, who may change it, and whether you can move the tool to a second source. “We will support you” does not say who owns the asset.
2. What output can you hold on this profile, and what else runs on that line?
Ask for pieces or meters per week at the wall you are buying, and which other profiles share the crew and the production line. A complete answer is a rate plus a statement of shared capacity. A factory-wide headline number describes every product they make, not your frame.
3. What is the lead time at our annual volume?
Separate sample lead time from the lead time at the monthly quantity on the purchase order. Include the weeks for a first article if the revision is new. Write both numbers down. A single “four weeks” that applied to a box of samples will miss the vessel when the order is a quarter of your module output.
4. What is the minimum order, and which changes move the price?
Ask for the minimum order on this drawing, the price break if you double it, and whether color, length, corner hardware, or a tighter tolerance is a different price. A complete answer is a small table. A single price with “depends” leaves finance unable to compare two suppliers. The wider checklist you use before the purchase order, including packaging and audit points, is in the OEM solar frame sourcing checklist.
Lots, Checks, and Reports
5. How does a lot trace back to alloy or compound, and when do you tell us it changed?
For aluminum, the answer names alloy and temper on the label. For GRPU, it names the compound code. In both cases, ask what counts as a change you must hear about before the next shipment: a new material lot family, a new tool, or a new corner method. A complete answer is a label example plus a notice rule. A quality manual with no label photo is not traceability.
6. What do you check on every lot, and what fails the lot?
Ask which dimensions are measured every lot (length, wall, hole position, corner closure) and what the reject rule is. Ask to see the photo standard for an acceptable corner. A complete answer is a control plan row you can audit. “100% inspection” without the characteristic and the gauge is a slogan.
7. Which test reports exist for this drawing revision?
Ask for the report numbers that match the revision on the quotation, and whether each sample was a profile, a corner, or a full module. For a GRPU buy, the pack you are looking for is mechanical load, insulation, salt mist, and UV, as set out in the testing checklist. For aluminum, ask for the mechanical and corrosion evidence your project actually requires. A report on another wall thickness does not answer this question.
Change, Packing, and After-Sales
8. If the wall, material, or corner changes, what do you retest before you ship?
A complete answer lists the tests that rerun and who approves the first shipment after the change. Tie it to your module certificate: if this frame sits on a certified bill of materials, your certification body has a delta rule too. The supplier’s silence is not that rule. Corner and clamp failures that show up when this step is left out are described in GRPU frame failure modes. The same discipline applies when an aluminum section changes.
9. How are the frames packed, and who pays for crushed corners?
Ask for the packing sketch: bundle size, corner protection, strap path, and the moisture note. Ask who replaces frames that arrive with open corners, and whether that replacement uses the same revision. A complete answer is a sketch plus a replacement clause. “Export packing” is not a sketch.
10. Who answers when our line holds a lot, and how fast?
Name a person, a backup, and a clock: hours to acknowledge, days to a disposition (use, sort, or return). Ask whether they will send someone to your framing line for a repeated defect. A complete answer fits in a contact table. A general sales mailbox with no clock means the lot sits in your quarantine while the module schedule moves.
11. What does the warranty cover, separate from any design-life statement?
Ask for the warranty term, the defects it includes, the exclusions, and the remedy (replace, credit). If the supplier also states a design life, such as a 25+ year target under intended use, ask them to keep that sentence in a different paragraph from the warranty. Record both. Mixing them is how a design target becomes an argument after a field crack.
12. Which plant will make this profile, and can we see that line first?
Ask for the factory address that will run the mass order, not the headquarters on the brochure. Ask for a visit or a live video of that line before the first mass shipment, including the corner step and the packing step. A complete answer is an address plus a date window. A showroom tour of a different workshop does not qualify the plant on the purchase order.
How to Score the Answers
Give each question one of three marks, written by procurement and quality together.
| Mark | What you received | Next step |
|---|---|---|
| Closed | A revision, a quantity, a report number, a name, or a clause you can attach to the order | File it with the RFQ |
| Open | A partial number, or a promise to send the document | Set a date. Do not schedule mass framing on it |
| Blocked | No owner for the drawing, no lot identity, or no person for a reject | Stop the vendor decision until the answer exists |
Score GRPU and aluminum bidders on the same sheet so a lower meter price cannot hide a blocked row. Two suppliers can both be acceptable. A single source is a choice you make after the blocked rows are gone, not before the meeting.
Keep the sheet for the annual review. Capacity and the named contact go stale. A supplier who was closed last year can be open this year if the plant or the compound changed. Ask questions 2, 5, 8, and 10 again before you renew the order.
What These Questions Do Not Replace
- They do not set a price target or a lead-time promise. Those come back on your RFQ, for your drawing and your volume.
- They do not choose GRPU or aluminum. Cost, corrosion, weight, and conductivity are a material decision. This list checks whether the company can supply whichever material you chose.
- They do not replace a pilot lot. Closed answers earn the pilot. The pilot earns the mass order.
- They do not publish a ranking of frame factories. Run the twelve questions on the vendors in your own bid. Weltrus will answer them for a named GRPU profile when you send the drawing and the annual quantity.
Send the 12 Questions with Your Drawing
Share the profile revision, annual piece count, and whether you are buying GRPU or comparing it with aluminum. Weltrus will reply in writing on ownership, capacity, lot checks, reports, and the contact for a held lot.
Frequently Asked Questions
What are the 12 questions for before locking a frame supplier?
Ask who owns the drawing and tooling, what output the line can hold, lead time at your volume, MOQ and price breaks, lot traceability, in-process checks, which test reports match the drawing, the retest rule after a change, packing and damage responsibility, a named contact for held lots, warranty scope versus any design-life statement, and which plant will make the profile.
Do the same 12 questions apply to GRPU and aluminum frame suppliers?
Yes. Capacity, lot identity, corner inspection, change control, and after-sales are the same meeting. Material-specific answers differ: alloy and temper for aluminum, compound code for GRPU, and a clamp note written for the wall you will buy.
What does a useful supplier answer look like?
A useful answer names a drawing revision, a quantity per week or month, a lead time at that quantity, a report number, or a person and a response time. File the answer with the purchase order. A slogan without those details stays off the approved-vendor list.
How is this list different from an RFQ or a test checklist?
The RFQ fixes the fields on the quote so prices compare. The test checklist fixes which reports must be in the folder. These 12 questions are what you ask in the supplier meeting about ownership, capacity, and who responds when a lot fails. Use all three before you name a single source.
When should the module OEM stop the vendor decision?
Stop when drawing ownership is unclear, mass-volume lead time is missing, lots cannot be traced, test reports name another revision, or nobody is named for a line reject. Finish those answers, then issue the purchase order.
