Give suppliers the same duty, flow range, approvals, communication and commercial terms before you compare unit prices.
Quick answer
- A RFQ that says “DN100 water meter” will come back five different prices, because your suppliers are quoting five different meters.
- Twelve fields decide the quote: quantity split, application, measured flow range, required Q1, allowed technology, connections, orientation, water quality, readout, communication, power, and approvals.
- The three lines most often missing are the pulse output definition, the radio frequency band for the installing country, and what happens when the battery dies.
- Ask for Q1 in litres per hour, not merely an accuracy class — here is why those two specifications decide the price.
- State your commercial terms explicitly: Incoterms, port, lead time, payment, warranty, spares. Otherwise each quote optimises something different.
- Score responses in your own table and reject “compliant” written where a number should be.
Two utilities can ask ten manufacturers for the same meter and receive quotes spanning a factor of five — then spend a week discovering why. Nothing dishonest happened. The suppliers each filled in a different set of blanks. Writing a water meter RFQ that produces comparable quotes is mostly a matter of closing those blanks in advance.
Why the spread happens
Each of the following is a legitimate answer to “DN100 water meter”:
- Technology. A mechanical Woltman and an ultrasonic bulk meter are both DN100. One costs several times the other and measures low flow differently.
- Turndown range. R80 and R400 are both “DN100”. They differ by how much water at the bottom of the range you can bill.
- Scope. One quote includes the communication module, another quotes the bare meter and mentions the module as an option.
- Approvals. Type approval testing, notified-body involvement and per-meter calibration certificates cost real money. Somebody has decided whether to include them.
- Commercial basis. EXW versus CIF versus DDP can move the headline figure by double digits before you compare anything.
The twelve fields that make quotes comparable
This table is the whole job. Each row is a blank your suppliers will otherwise fill themselves.
| # | Field | What to write | What happens if you leave it out |
|---|---|---|---|
| 1 | Quantity per size | Exact count per diameter, and the expected call-off schedule | Price tiers are guessed; nobody quotes the realistic volume |
| 2 | Application | Domestic, estate inlet, DMA, industrial, or irrigation | Suppliers pick a technology family for you |
| 3 | Measured flow range | Minimum and maximum in m³/h, including night line | Meters get sized on pipe diameter, which is the classic error |
| 4 | Required Q1 or R value | State Q3 and the minimum flow you must register | The single biggest silent price driver after technology |
| 5 | Technology allowed | Open, or restricted to mechanical, or restricted to ultrasonic | Mixed bids that cannot be scored against each other |
| 6 | End connections | Thread standard (ISO 228-1) or flange (EN 1092-2, ANSI B16.1) | Site adapters, delays, and meters that do not fit old threads |
| 7 | Orientation | H for horizontal, V for vertical installation | Registration errors that look like meter faults for years |
| 8 | Water quality and temperature | Potable, sediment load, scaling tendency, T30 to T90 | Fouled ultrasonic paths or premature mechanical wear |
| 9 | Readout | Register type, units, whether the index can be changed later | Units arriving on site do not match your billing system |
| 10 | Communication | None, pulse, wired M-Bus, wireless M-Bus, LoRaWAN, or NB-IoT | Modules quoted as extras; the true comparison collapses |
| 11 | Power and battery life | Required years of operation, and whether it is replaceable | A renewal cost arrives in year ten with no budget line for it |
| 12 | Approvals | MID, national type approval, utility list, calibration certificates | Cheapest quote excludes the testing you actually need |
The three lines most RFQs leave out
In our experience these cause more rework than all twelve fields above, because the omission only becomes visible after delivery:
- Pulse output definition. Litres per pulse, pulse width, and whether the output is reed switch or open collector. A logger configured for 10 L/pulse on a meter delivering 100 L/pulse under-reads by a factor of ten, and nobody notices until the first reconciliation.
- Radio frequency band. LoRaWAN uses different regional plans — EU868, US915, AU915, AS923, IN865 — and NB-IoT depends on the operator’s band in your country. Quote for the installing country, not the factory’s default.
- Battery replacement plan. A sealed meter with a non-replaceable ten-year battery is a full replacement cost scheduled into year ten. Ask whether the battery can be replaced in the field, by whom, and at what cost — before you order 20,000 units.
Where tenders and direct purchases differ
A formal tender and a direct enquiry want different things, and suppliers read them differently. In a tender, anything you do not mark as mandatory will be read as negotiable — and anything marked mandatory without a measurable test invites a complaint from the bidder who loses. Write mandatory rows with the test method next to them.
In a direct purchase you can be far more efficient: send the specification, state what is fixed and what you want advice on, and ask for two options rather than one. Asking explicitly for the cheaper alternative that still meets the nine fields you care about will teach you more about your own specification than three rounds of clarification emails.
One regional note worth knowing: North American specifications frequently reference the AWWA C700 family of cold water meter standards alongside ISO 4064, and utility lists there often name a particular standard outright. If you are writing for both markets, say which applies where — otherwise every supplier picks their home standard.
A specification block you can copy
Drop-in enquiry block
Paste into your enquiry and fill the brackets. Placeholders in pink.
- Size and quantity: DN[ ] — [ ] units delivered against this schedule: [ ]
- Duty: [domestic / bulk / DMA / industrial / irrigation]; continuous Q3 target [ ] m³/h, minimum continuous [ ] m³/h, peak [ ] m³/h
- Low flow: minimum flow to be registered within accuracy limits: [ ] L/h
- Technology: [open / mechanical only / ultrasonic only]
- Connection: [thread ISO 228-1 / flange EN 1092-2 / ANSI B16.1 class 125]; orientation [H / V]
- Water: [potable / irrigation with sediment]; temperature class [T30 / T50 / T70]
- Output: [none / pulse at [ ] L per pulse / wired M-Bus / LoRaWAN regional plan [ ] / NB-IoT bands [ ]]
- Power: minimum [ ] years battery life; field-replaceable [yes / no]
- Approvals: [MID Annex MI-001 / national approval no. [ ] / utility list]; calibration certificate [per batch / per meter]
- Documents: manuals in [English / other], conformity declaration, packing list language
- Commercial: Incoterms [ ] to port [ ], requested delivery [ ], payment terms [ ], warranty [ ] months, spares kit [yes / no]
If prepaid is in scope
Prepaid metering adds a whole second specification. Add these before you send:
- Token standard. STS (IEC 62055-41) keeps your customer locked to nothing and lets you change supplier later. Proprietary token schemes usually do not.
- Top-up channels. Keypad entry, vending stations, mobile money, USSD, or an app. Each one implies different work and different cost.
- Valve behaviour. What position the valve takes when credit runs out or the battery fails — and whether it can be overridden.
- Who runs the vending server. Cloud versus local, who owns the data, and what the annual fee is per meter.
Our explanation of how STS prepaid metering works covers the mechanism in detail if you need to brief colleagues first.
Evaluating what comes back
- Rebuild the responses in your own scoring table. Columns should be your twelve fields, not the supplier’s layout.
- Reject the word “compliant” where a number belongs. “Compliant with Q1 requirements” is not an answer; 6.3 L/h is.
- Verify the approval. Take the certificate number and check it with the issuing body rather than the supplier.
- Order samples before the batch. One per size, tested on your own bench or your own installation.
- Score total cost, not unit price. Unit price plus installation plus expected replacement plus any platform fee per meter per year.
Frequently asked questions
How much detail is too much?
None of the twelve fields is a problem. What slows suppliers down is uncertainty about which fields are mandatory and which are preferences — mark each row “required” or “preferred” and you will get faster, cleaner answers.
Should I send my own spreadsheet template?
Yes, if you have one. A supplier completing your table gives you numbers you can sort; a supplier interpreting your prose gives you a document you have to read twice.
Do I need to specify the accuracy class?
Specify it only if your regulation requires it. Otherwise specify Q3 and the minimum flow you must register, and let suppliers propose the combination. You will get better matches and clearer pricing.
What lead time should I ask for?
Ask for it as a question rather than a requirement: “lead time for first shipment and for full quantity”. Sample or pilot quantities often ship much faster than production volume, which is worth knowing before you plan the rollout.
What to send us
- The twelve fields above — or simply the filled-in block, which is faster.
- Any indication of the overall programme size, even approximate, so we can quote in realistic quantity tiers.
- Your target approval and destination market.
- Whether this is a tender response or a direct purchase, since the document set differs.
We can quote the same duty against mechanical and ultrasonic bodies so you can see the real difference rather than two different silences. Browse what we supply and can quote, or start from the product line at water meters and flow meters. Then send us the specification — a complete RFQ usually gets a priced answer back within one working day.