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Views: 0 Author: Site Editor Publish Time: 2026-11-04 Origin: Site
A quotation request that says "I need a 2.2 kW VFD" will produce a price, a lead time, and a coin flip on whether the drive is right. The supplier cannot know from that line whether the motor is single or three phase, whether the load starts heavy, whether the cable run is four metres or four hundred, or whether the buyer needs a CE declaration in the box.
Five numbers fix this. They come off the motor nameplate and out of the site conditions, and having them ready turns a two-week back-and-forth into one reply.
Power is on every nameplate and it is the number everyone leads with. It is also the least informative on its own.
A 2.2 kW motor can be a single-phase 220 V unit drawing around ten amps, or a three-phase 380 V unit drawing around five. Those two need different drive models from the same series, and the AS2 range covers both — single-phase 220 V from 0.4 to 2.2 kW, three-phase 380 V from 0.75 to 7.5 kW. Quote the power alone and the supplier has to guess which half of the range applies.
What to send: power in kW, plus phase count and voltage.
This is the number that actually sizes the drive, and it is the one most often left out.
Drive ratings are current ratings. A motor nameplate that reads 2.2 kW / 5.0 A on a 380 V three-phase supply needs a drive whose continuous output current is at least 5.0 A — and the model number does not always make that obvious, because different makers put different current in a frame of the same nominal power.
Two motors of the same power from different manufacturers can differ by fifteen percent on full-load current. Buying on power alone means buying a drive that is either marginal or unnecessarily large.
What to send: full-load current in amps, from the nameplate, not from a catalogue.
Tell the supplier what the motor turns. Not the industry, not the application name — what it physically drives.
"Pump" is not enough. A centrifugal pump is a variable-torque load that a V/F drive handles easily. A positive-displacement pump is a high-breakaway-torque load that may need a larger frame. "Conveyor" ranges from a light belt that starts empty to a screw that starts full of material, and those two need different overload margins.
The reason this matters is that drive selection is not one calculation, it is two: continuous current for the running load, and overload capacity for the starting condition. The duty is what tells the supplier which overload figure to check against.
For the AS2, the G-type rating carries 150% of rated current for 60 seconds and 150% starting torque. Whether that is enough depends entirely on what the motor is starting against.
What to send: one sentence — "drives a belt conveyor that starts loaded, about six starts per hour".
Nobody puts this in a first enquiry, and it is the cause of a large share of site problems afterwards.
Long motor cables distort the output waveform. On short runs the effect is negligible; beyond roughly fifty metres it starts to matter, and the usual fix is an output reactor. If the supplier knows the run is 120 metres before shipping, the reactor can go in the same box. If they find out after installation, it becomes a separate order and a second installation visit.
The same applies to where the drive will physically sit. A panel inside a clean control room and a panel beside a dust extraction duct are the same drive model but not the same installation.
What to send: approximate cable length, and where the drive will be mounted.
This is the number buyers forget until the container is booked.
Does the destination market require a CE declaration? Does the buyer's own customer require a test certificate with the serial number? Is the drive going into a machine that will itself be certified, in which case the drive's EMC declaration has to match the machine's category?
For an OEM shipping machines into Europe, this is not an afterthought — it is part of the specification. For a distributor stocking spares, it may be irrelevant. Either way, saying it in the first message avoids a second shipment of documents.
What to send: which market it ships to, and whether certificates are needed with the goods.
Take one motor: three-phase 380 V, 2.2 kW, nameplate 5.0 A. Two buyers, two enquiries, two different quotations.
Buyer A drives a centrifugal pump with PID pressure control, cable run 15 m, panel in a pump room. The drive is a 2.2 kW three-phase model, no accessories, parameters pre-set for PID on pressure. One line on the quotation, one lead time.
Buyer B drives a screw conveyor that starts full of material, six starts per hour, cable run 60 m, panel beside the machine. Same motor, but three things change. The starting current is higher, so the overload margin has to be checked against 150% for 60 seconds rather than assumed. The 60 m run is past the point where an output reactor is cheap insurance, so one goes on the quotation. Six starts an hour means the drive spends real time in the acceleration range, so the thermal margin matters more than the nameplate power suggests.
Buyer B may end up with the next frame size up, plus a reactor. That is not upselling - it is the difference between a drive that runs for five years and one that trips every Monday morning and gets blamed on the supplier.
The five numbers are what separate those two quotations. Without the duty and the cable length, both buyers get the same price and one of them gets the wrong drive.
A quotation that can be checked without a second email has six lines: model and full ordering code, rated output current, accessory list or "none", enclosure and mounting, lead time, and what documentation ships with the goods.
If any of those is missing, ask before ordering. A quotation without the current rating is a price, not a specification.
The enquiry that gets a correct quotation on the first reply looks like this:
Three-phase 380 V, 2.2 kW motor, nameplate 5.0 A, drives a centrifugal pump with PID pressure control, cable run about 15 m, drive mounted in a panel in a pump room. Shipping to Poland, CE declaration needed. Quantity 20, OEM branding on the label.
That is four lines. It answers all five numbers and adds the two commercial facts that decide the price. Compare it with "need 2.2 kW VFD, please quote" — the second message will produce three clarifying emails and a quotation that may still be wrong.
Once the five are known, three things get decided:
The model. Power range, phase version and current rating narrow the catalogue to one or two entries. On the AS2, single-phase 220 V covers 0.4–2.2 kW and three-phase 380 V covers 0.75–7.5 kW across ten models.
The accessories. Output reactor for long cables, braking unit for high-inertia stops, enclosure for dusty locations. These are decided by numbers four and five, and they are cheaper bought with the drive than added later.
The parameters. A drive shipped with the ramp times, carrier frequency and V/F curve pre-set for the buyer's machine saves commissioning time on every unit in the order. That requires knowing the duty, which is number three.
The AS2 is a V/F drive for constant-speed and variable-torque duties in the 0.4–7.5 kW range: conveyors, pumps, fans and processing equipment. It has 0.1–400 Hz output, 150% starting torque, built-in PID and PLC, and natural convection cooling in an IP20 panel-mount housing.
If the duty needs torque at zero speed — a hoist, a winder, a machine that must hold position — the AS2 is the wrong drive and we will say so.
Send the five numbers and we will come back with the model, the accessory list if any, the lead time and the price. Sample orders and OEM branding are available; the datasheet and wiring diagram go out with the quotation.
See the AS2 series specification and model list for the full terminal layout and technical data.
