Menu
Your cart is empty
Looks like you haven't added anything to your cart yet
Grundfos CME Variable Speed Multistage Pumps
Grundfos CME 10-G Horizontal Multistage Pump, 316 Stainless Steel
Grundfos
Grundfos CME 10-G Horizontal Multistage Pump, 316 Stainless Steel
- Price
- From $3,645.36
Grundfos CME 10-I Horizontal Multistage Pump, 304 Stainless Steel
Grundfos
Grundfos CME 10-I Horizontal Multistage Pump, 304 Stainless Steel
- Price
- From $3,321.36
Grundfos CME 10-A Horizontal Multistage Pump, Cast Iron / 304 Stainless Steel
Grundfos
Grundfos CME 10-A Horizontal Multistage Pump, Cast Iron / 304 Stainless Steel
- Price
- From $2,887.92
Grundfos CME 5-G Horizontal Multistage Pump, 316 Stainless Steel
Grundfos
Grundfos CME 5-G Horizontal Multistage Pump, 316 Stainless Steel
- Price
- From $3,160.80
Grundfos CME 5-I Horizontal Multistage Pump, 304 Stainless Steel
Grundfos
Grundfos CME 5-I Horizontal Multistage Pump, 304 Stainless Steel
- Price
- From $2,854.80
Grundfos CME 5-A Horizontal Multistage Pump, Cast Iron / 304 Stainless Steel
Grundfos
Grundfos CME 5-A Horizontal Multistage Pump, Cast Iron / 304 Stainless Steel
- Price
- From $2,578.33
Grundfos CME 3-G Horizontal Multistage Pump, 316 Stainless Steel
Grundfos
Grundfos CME 3-G Horizontal Multistage Pump, 316 Stainless Steel
- Price
- From $3,011.76
Grundfos CME 3-I Horizontal Multistage Pump, 304 Stainless Steel
Grundfos
Grundfos CME 3-I Horizontal Multistage Pump, 304 Stainless Steel
- Price
- From $2,778.48
Grundfos CME 3-A Horizontal Multistage Pump, Cast Iron / 304 Stainless Steel
Grundfos
Grundfos CME 3-A Horizontal Multistage Pump, Cast Iron / 304 Stainless Steel
- Price
- From $2,490.48
Grundfos CME Variable Speed Multistage Pumps
Grundfos CME Variable Speed Multistage Pumps
The CM pump end with an MLE drive on top. Close-coupled, end-suction multistage pumps that lie on their feet and vary their own speed instead of throttling against a valve. Three frames, three material grades, NPT threaded ports.
176part numbers
16.4-52.8GPM rated flow
306 ftmaximum rated head
2900-4000rpm speed band
51model and material pairs
The Same Pump End, With The Drive Built In
Grundfos builds the CME on the CM pump end. The hydraulics are shared — we checked all 51 published model and material pairs against their CM equivalents and the rated head agrees on every one, to within 0.01 m — the last digit Grundfos prints — and the difference is the motor. A CME carries a Grundfos MLE permanent-magnet motor with the frequency converter inside its terminal box, so the pump slows down to meet a lighter demand rather than running flat out against a throttling valve. Grundfos publishes a rated speed band per model, 2900 rpm to 4000 rpm across this range, where a fixed-speed CM publishes one number.
That matters where demand swings. Throttling a fixed-speed pump wastes energy across the valve; slowing the pump avoids generating it. Where the duty genuinely sits at one point all day, the fixed-speed CM is the better buy and we will say so. The footprint argument is unchanged from CM: the pump lies horizontal on its feet with the suction on the end, which suits a plant room where headroom is short and floor space is not, and both ports are NPT female threads, so nothing has to be ordered alongside the pump.
We supply the full CME 3, CME 5 and CME 10 range in the correct US 60 Hz build — 176 part numbers across three frames and all three material grades, in AQQE or AQQV seals. Send us the flow, the required boost, the inlet pressure, the liquid, how the demand behaves and the available voltage and we will size it against the published Grundfos curve and give you the part number and lead time — call 1-888.510.4036.
Genuine Grundfos equipment, factory-new in original packaging — sold and supported by Watermain Supply, an independent industrial supplier.
Three Material Grades
The drive is the same on all three. The material code is still the decision that sets the pressure rating, the temperature ceiling and the approvals — the frame only sets the flow.
CME-A
Cast Iron / 304 · 32 part numbers
16.4/24.8/52.8 GPMrated flow
64-191 ftrated head
3/4 to 5 HPmotor range
145 psimax pressure
Cast iron pump housing, AISI 304 internals, with an integrated MLE variable-speed motor. Three frames at 60 Hz — CME 3 at 16.4 GPM, CME 5 at 24.8 GPM and CME 10 at 52.8 GPM — with rated head from 64 ft to 191 ft. Rated 145 psi maximum operating pressure.
Key specifications
- Rated flow 16.4 / 24.8 / 52.8 GPM at 60 Hz; rated head 64-191 ft
- 3/4 to 5 HP (P2) MLE permanent-magnet motor, frequency converter built in
- Rated speed bands 2900-4000, 3400-4000 and 3500-4000 rpm, published per model rather than as one fixed speed
- Maximum operating pressure 145 psi
- AQQE seal to 194 °F; AQQV seal to 194 °F
- WRAS, ACS, NSF61 drinking-water approvals
- Minimum efficiency index (MEI) 0.7 as published
- 32 part numbers; shipping weight 40-141 lb
Best forVariable-demand water transfer, pressure boosting, irrigation and washdown on clean potable water, and cooling loops where an all-stainless liquid path is not required and the lowest cost per GPM is.
CME-I
All AISI 304 · 72 part numbers
16.4/24.8/52.8 GPMrated flow
53-306 ftrated head
3/4 to 7-1/2 HPmotor range
232 psimax pressure
AISI 304 stainless throughout the liquid path, with an integrated MLE variable-speed motor. Three frames at 60 Hz — CME 3 at 16.4 GPM, CME 5 at 24.8 GPM and CME 10 at 52.8 GPM — with rated head from 53 ft to 306 ft. Rated 232 psi maximum operating pressure.
Key specifications
- Rated flow 16.4 / 24.8 / 52.8 GPM at 60 Hz; rated head 53-306 ft
- 3/4 to 7-1/2 HP (P2) MLE permanent-magnet motor, frequency converter built in
- Rated speed bands 2900-4000, 3400-4000 and 3500-4000 rpm, published per model rather than as one fixed speed
- Maximum operating pressure 232 psi
- AQQE seal to 248 °F, 194 °F on CME 3-8, CME 3-9, CME 5-8 and CME 10-5; AQQV seal to 194 °F
- WRAS, ACS, NSF61, UBA drinking-water approvals
- Minimum efficiency index (MEI) 0.7 on CME 3 and CME 5; 0.52 on CME 10 as published
- 72 part numbers; shipping weight 41-142 lb
Best forConstant-pressure potable boosting where iron pick-up is unacceptable, boiler feed and condensate, filtration and softening skids, and food and light process duty on clean, low-chloride supplies.
CME-G
All AISI 316 · 72 part numbers
16.4/24.8/52.8 GPMrated flow
53-306 ftrated head
3/4 to 7-1/2 HPmotor range
232 psimax pressure
AISI 316 stainless throughout the liquid path, with an integrated MLE variable-speed motor. Three frames at 60 Hz — CME 3 at 16.4 GPM, CME 5 at 24.8 GPM and CME 10 at 52.8 GPM — with rated head from 53 ft to 306 ft. Rated 232 psi maximum operating pressure.
Key specifications
- Rated flow 16.4 / 24.8 / 52.8 GPM at 60 Hz; rated head 53-306 ft
- 3/4 to 7-1/2 HP (P2) MLE permanent-magnet motor, frequency converter built in
- Rated speed bands 2900-4000, 3400-4000 and 3500-4000 rpm, published per model rather than as one fixed speed
- Maximum operating pressure 232 psi
- AQQE seal to 248 °F, 194 °F on CME 3-8, CME 3-9, CME 5-8 and CME 10-5; AQQV seal to 194 °F
- WRAS, ACS, NSF61, UBA drinking-water approvals
- Minimum efficiency index (MEI) 0.7 on CME 3 and CME 5; 0.52 on CME 10 as published
- 72 part numbers; shipping weight 41-142 lb
Best forSoftened, brackish and chloride-bearing water, coastal sites, reverse osmosis feed and permeate, chemical dosing, and food, beverage and pharmaceutical process duty.
CME-A vs CME-I vs CME-G
Pick the grade on the liquid and the pressure, then the frame on the flow, then the stack on the head.
| Â | CME-A | CME-I | CME-G |
|---|---|---|---|
| Pump housing | Cast iron, EN-GJL-200 | AISI 304 | AISI 316 |
| Liquid path | Cast iron and 304 | All 304 | All 316 |
| Max operating pressure | 145 psi | 232 psi | 232 psi |
| AQQE temperature ceiling | 194 °F | 248 °F, 194 °F on CME 3-8, CME 3-9, CME 5-8 and CME 10-5 | 248 °F, 194 °F on CME 3-8, CME 3-9, CME 5-8 and CME 10-5 |
| AQQV temperature ceiling | 194 °F | 194 °F | 194 °F |
| Drinking-water approvals | WRAS, ACS, NSF61 | WRAS, ACS, NSF61, UBA | WRAS, ACS, NSF61, UBA |
| Frequency converter | Built in | Built in | Built in |
| Stage options, CME 3 | 4 | 8 | 8 |
| Stage options, CME 5 | 4 | 7 | 7 |
| Stage options, CME 10 | 3 | 5 | 5 |
| Part numbers | 32 | 72 | 72 |
Quick rule. Chlorides decide between 304 and 316 — the molybdenum in 316 resists chloride pitting and 304 has none, so softened, brackish and coastal water calls for CME-G. Iron pick-up decides between cast iron and stainless: on potable water that sits idle, CME-A can bloom rust into the first draw where CME-I will not. And if the system runs above 145 psi, cast iron is out on the pressure rating alone. The stainless builds also carry more stages — up to 8 on CME 3 against 4 on cast iron — so the tallest heads are stainless only.
Published Duty Points
Rated flow, rated head, pressure rating and rated speed band as Grundfos publishes them for the US 60 Hz build, for every model in every material. These are the nominal figures, not a curve.
| Model | Grade | Rated flow (GPM) | Rated head (ft) | Rated head (m) | Max pressure (psi) | Rated speed |
|---|---|---|---|---|---|---|
| CME 3-2 | CME-A | 16.4 | 64 | 19.51 | 145 | 2900-4000 rpm |
| CME 3-3 | CME-A | 16.4 | 97 | 29.68 | 145 | 2900-4000 rpm |
| CME 3-4 | CME-A | 16.4 | 131 | 39.86 | 145 | 2900-4000 rpm |
| CME 3-5 | CME-A | 16.4 | 164 | 50.03 | 145 | 2900-4000 rpm |
| CME 3-2 | CME-I | 16.4 | 63 | 19.1 | 232 | 2900-4000 rpm |
| CME 3-3 | CME-I | 16.4 | 96 | 29.27 | 232 | 2900-4000 rpm |
| CME 3-4 | CME-I | 16.4 | 129 | 39.45 | 232 | 2900-4000 rpm |
| CME 3-5 | CME-I | 16.4 | 163 | 49.62 | 232 | 2900-4000 rpm |
| CME 3-6 | CME-I | 16.4 | 196 | 59.8 | 232 | 2900-4000 rpm |
| CME 3-7 | CME-I | 16.4 | 230 | 69.97 | 232 | 2900-4000 rpm |
| CME 3-8 | CME-I | 16.4 | 263 | 80.15 | 232 | 3400-4000 rpm |
| CME 3-9 | CME-I | 16.4 | 296 | 90.32 | 232 | 3500-4000 rpm |
| CME 3-2 | CME-G | 16.4 | 63 | 19.1 | 232 | 2900-4000 rpm |
| CME 3-3 | CME-G | 16.4 | 96 | 29.27 | 232 | 2900-4000 rpm |
| CME 3-4 | CME-G | 16.4 | 129 | 39.45 | 232 | 2900-4000 rpm |
| CME 3-5 | CME-G | 16.4 | 163 | 49.62 | 232 | 2900-4000 rpm |
| CME 3-6 | CME-G | 16.4 | 196 | 59.8 | 232 | 2900-4000 rpm |
| CME 3-7 | CME-G | 16.4 | 230 | 69.97 | 232 | 2900-4000 rpm |
| CME 3-8 | CME-G | 16.4 | 263 | 80.15 | 232 | 3400-4000 rpm |
| CME 3-9 | CME-G | 16.4 | 296 | 90.32 | 232 | 3500-4000 rpm |
| CME 5-2 | CME-A | 24.8 | 70 | 21.36 | 145 | 2900-4000 rpm |
| CME 5-3 | CME-A | 24.8 | 108 | 32.77 | 145 | 2900-4000 rpm |
| CME 5-4 | CME-A | 24.8 | 145 | 44.19 | 145 | 2900-4000 rpm |
| CME 5-5 | CME-A | 24.8 | 182 | 55.6 | 145 | 3400-4000 rpm |
| CME 5-2 | CME-I | 24.8 | 70 | 21.37 | 232 | 2900-4000 rpm |
| CME 5-3 | CME-I | 24.8 | 108 | 32.78 | 232 | 2900-4000 rpm |
| CME 5-4 | CME-I | 24.8 | 145 | 44.2 | 232 | 2900-4000 rpm |
| CME 5-5 | CME-I | 24.8 | 182 | 55.61 | 232 | 3400-4000 rpm |
| CME 5-6 | CME-I | 24.8 | 220 | 67.03 | 232 | 3500-4000 rpm |
| CME 5-7 | CME-I | 24.8 | 257 | 78.44 | 232 | 3500-4000 rpm |
| CME 5-8 | CME-I | 24.8 | 295 | 89.85 | 232 | 3400-4000 rpm |
| CME 5-2 | CME-G | 24.8 | 70 | 21.37 | 232 | 2900-4000 rpm |
| CME 5-3 | CME-G | 24.8 | 108 | 32.78 | 232 | 2900-4000 rpm |
| CME 5-4 | CME-G | 24.8 | 145 | 44.2 | 232 | 2900-4000 rpm |
| CME 5-5 | CME-G | 24.8 | 182 | 55.61 | 232 | 3400-4000 rpm |
| CME 5-6 | CME-G | 24.8 | 220 | 67.03 | 232 | 3500-4000 rpm |
| CME 5-7 | CME-G | 24.8 | 257 | 78.44 | 232 | 3500-4000 rpm |
| CME 5-8 | CME-G | 24.8 | 295 | 89.85 | 232 | 3400-4000 rpm |
| CME 10-1 | CME-A | 52.8 | 65 | 19.69 | 145 | 2900-4000 rpm |
| CME 10-2 | CME-A | 52.8 | 128 | 39.01 | 145 | 3500-4000 rpm |
| CME 10-3 | CME-A | 52.8 | 191 | 58.34 | 145 | 3500-4000 rpm |
| CME 10-1 | CME-I | 52.8 | 53 | 16.12 | 232 | 2900-4000 rpm |
| CME 10-2 | CME-I | 52.8 | 116 | 35.44 | 232 | 3500-4000 rpm |
| CME 10-3 | CME-I | 52.8 | 180 | 54.77 | 232 | 3500-4000 rpm |
| CME 10-4 | CME-I | 52.8 | 243 | 74.1 | 232 | 3500-4000 rpm |
| CME 10-5 | CME-I | 52.8 | 306 | 93.42 | 232 | 3500-4000 rpm |
| CME 10-1 | CME-G | 52.8 | 53 | 16.12 | 232 | 2900-4000 rpm |
| CME 10-2 | CME-G | 52.8 | 116 | 35.44 | 232 | 3500-4000 rpm |
| CME 10-3 | CME-G | 52.8 | 180 | 54.77 | 232 | 3500-4000 rpm |
| CME 10-4 | CME-G | 52.8 | 243 | 74.1 | 232 | 3500-4000 rpm |
| CME 10-5 | CME-G | 52.8 | 306 | 93.42 | 232 | 3500-4000 rpm |
Reading these figures. Head is stated in feet; divide by 2.31 for psi, or multiply psi by 2.31 for feet. Elevation costs 0.433 psi per foot of lift. The rated speed is a band because the drive varies it — the head figure alongside is the nominal duty point, not a ceiling the pump reaches at every speed. The cast-iron rows are not a copy of the stainless ones: they read about 1.3-1.4 ft higher on every CME 3 and about 11.7 ft higher on every CME 10, and identical on every CME 5. That is what Grundfos publishes, not a rounding artefact, which is why each grade carries its own figures rather than sharing a table. For the flow and head at a specific point on the curve, request the manufacturer curve for the part number and we will send it.
Sizing a CME
A pump curve plots what the pump adds to the pressure already at its inlet. Size on the boost required, never on the pressure wanted.
- Find the peak flow. For residential, count water supply fixture units and convert with the Hunter curve in IPC Table 604.3. For light commercial, use the IAPMO Water Demand Calculator. Guessing high here is the most expensive mistake in the exercise.
- Work out the required boost. Required boost = target pressure at the highest fixture + 0.433 psi per foot of elevation + friction loss through pipe, fittings and any treatment − the inlet pressure you can count on at peak demand.
- Worked example. A building wants 45 psi at a fixture 30 ft above the pump. Friction through the riser and meter is 7 psi. The main holds 38 psi at peak. Required boost = 45 + (30 × 0.433) + 7 − 38 = 27 psi, which is 62 ft of head. At 25 GPM that lands on the shortest CME 5 stack.
- Size on the peak, then let the drive handle the rest. This is the part that differs from a fixed-speed CM. Pick the model that covers the worst case, because the drive can slow down for lighter demand but cannot exceed the curve. Oversizing is still a mistake — a pump idling at the bottom of its band is paying for capacity it never uses.
- Pick the frame from the flow. 16.4 GPM for CME 3, 24.8 GPM for CME 5, 52.8 GPM for CME 10. Then choose the stage count that covers the head. Going up a frame to cure weak pressure at a single outlet is the usual mis-buy.
- Choose the grade on the liquid, then check the pressure. Chlorides mean CME-G. Potable water with no iron pick-up allowed means CME-I. Otherwise CME-A is the lowest cost — provided the system stays under its 145 psi rating, against 232 psi on the stainless builds, and provided the head you need is inside the shorter cast-iron range.
- Check the liquid temperature against the seal. On the stainless builds AQQE reaches 248 °F and AQQV 194 °F; on cast iron both are 194 °F. The seal changes a published limit, so it is a specification decision rather than a preference.
- Confirm the electrical supply. 200-240 V single phase, 200-240 V three phase or 440-480 V three phase, fixed per part number on the MLE motor and not rewireable between phases.
- Decide whether you want closed-loop control. A CME runs at a set speed out of the box. Add a pressure sensor to the built-in converter and it holds constant pressure instead. Tell us if you want that from the start.
The 70 percent rule. If the duty point sits above about 70 percent of a model's rated head, step up to the next stack. It leaves room for pipe scaling, a dirty strainer and the day the inlet pressure sags. On a variable-speed pump it also keeps some band in reserve — a CME already at the top of its speed range has nothing left to give when the system gets dirty.
Selection Guide
A starting point, not a substitute for sizing. Send us the numbers and we will confirm the part number.
| Application | Typical demand | Start with | Notes |
|---|---|---|---|
| Variable-demand transfer and boosting, clean water | 15-17 GPM | CME 3-A | Lowest cost per GPM. Confirm the system stays under 145 psi. |
| Constant-pressure potable boosting | 15-17 GPM | CME 3-I | No cast iron in the liquid path, 232 psi, and a sensor gets you closed-loop control. |
| Softened or coastal water | 15-17 GPM | CME 3-G | 316 for chloride resistance. The 304 build risks pitting. |
| Irrigation zones with changing demand | 22-26 GPM | CME 5-A | The drive suits zone-by-zone switching. Check washdown chemistry against the seal. |
| Boiler feed and condensate | 22-26 GPM | CME 5-I | AQQE to 248 °F. Check the model — the tallest stack falls back. |
| RO feed and permeate | 22-26 GPM | CME 5-G | 316 throughout. Permeate is aggressive despite being clean. |
| Cooling and process transfer | 45-53 GPM | CME 10-I | 5 stage options against 3 on the cast-iron build. |
| Chemical dosing | Any | CME-G | Send the liquid and concentration — the seal may decide it, not the stainless grade. |
| Steady duty at one point all day | Any | CM, not CME | The drive is a premium you would not use. Same hydraulics, fixed speed. |
| Short floor space, high ceiling | Any | CRE, not CME | The vertical range stands upright and reaches far higher heads and pressures. |
What The CME Build Gives You
Drive Inside The Terminal Box
The frequency converter is built into the MLE motor on every model and material in this range. No external drive to specify, no panel space to find, no motor cable to screen, and no separate commissioning visit for the drive.
MLE Permanent-Magnet Motor
A Grundfos MLE motor rated efficiency class IE5 to IEC 60034-30-2 — a permanent-magnet design with the high-efficiency drive integrated, rather than an induction motor with a converter bolted on.
Speed As A Band, Not A Number
Grundfos publishes a rated speed range per model, 2900 to 4000 rpm across this range, because the pump sets its own speed to meet the demand instead of running at one fixed speed against a valve.
Sensor-Ready For Constant Pressure
Connect a pressure sensor to the built-in converter and the pump holds a pressure setpoint rather than a speed. It can be added later, so a transfer duty today can become a constant-pressure duty without changing the pump.
Horizontal, Close-Coupled
Motor and pump end on a single shaft, mounted on feet. Nothing to align on installation, no separate baseplate to grout, and a low profile that fits under pipework and mezzanines where an upright CRE will not.
Threaded Ports, Nothing Extra
NPT female on suction and discharge across every build — 1 in suction and 1 in discharge on CME 3, 1-1/4 in suction and 1 in discharge on CME 5 and 1-1/2 in suction and 1-1/2 in discharge on CME 10. No companion flanges, no couplings and no gaskets to order with the pump.
Three Material Grades
Cast iron with 304 internals, all 304, or all 316. The grade is a specification decision, not a finish: it sets the pressure rating and the drinking-water approvals as well as the corrosion resistance.
Curve Tolerance ISO9906:2012 3B
Published duty points carry the grade 3B tolerance band, the same basis as the rest of the Grundfos multistage range, so a CME figure and a CM or CR figure can be compared directly. Ambient rating -4 to 131 °F.
CME Against The Rest Of The Range
Four answers to overlapping duties. The figures below come from our own product data for each range, not from memory.
| Â | CME | CM | CRE / CRIE / CRNE | CR / CRI / CRN |
|---|---|---|---|---|
| Orientation | Horizontal, on feet | Horizontal, on feet | Vertical, in-line ports | Vertical, in-line ports |
| Speed control | Built-in MLE drive | Fixed speed | Built-in MLE drive | Fixed speed |
| Pump end | Shared with CM | Shared with CME | Shared with CR | Shared with CRE |
| Connections | NPT threaded, nothing extra | NPT threaded, nothing extra | Oval NPT or ANSI flanged | Oval, Victaulic or ANSI flanged |
| Companion hardware | None needed | None needed | Separate on flanged | Separate on grooved and flanged |
| Grades offered | Cast iron/304, 304, 316 | Cast iron/304, 304, 316 | Cast iron/304, 304, 316 | Cast iron/304, 304, 316, titanium |
| Best for | Short headroom, swinging demand | Short headroom, steady duty | Tight floor plan, swinging demand | Tight floor plan, higher pressure |
Where the vertical range still wins. On pressure and reach. CR runs to 362 psi on its flanged builds and far higher heads than any CME stack, and it offers a titanium grade the CME range does not. If the duty needs either, CME is the wrong platform however convenient the footprint. And where the demand genuinely sits at one point all day, a fixed-speed CM does the same hydraulic work without paying for a drive.
Service Kits
Grundfos lists a service kit against every CME part number — 10 distinct kits cover this range.
The kit is a separate part number and is not supplied with the pump. It follows the seal and the material as well as the frame, so the same frame in AQQE and AQQV takes different kits. Quote the pump part number when you order and we will match the correct kit and confirm lead time. Kit part numbers are published on each product page in this collection.
The Grundfos CM, CME and Boosters Service Kit Catalogue in the Documents section below lists what each kit contains. Shaft seals, neck rings, O-ring sets and motor bearing kits are also available individually, identified from the pump nameplate — for pumps we supplied and for ones we did not.
Documentation & Parts
Published Grundfos literature for the range, linked on every product page in this collection.
CM, CME Data Booklet
CME Installation and Operating Instructions
MLE Motor Data Sheet
CM, CME and Boosters Service Kit Catalogue
Drawings & Submittals
Dimensional drawings and a factory submittal package are available on request — email sales@watermainsupply.com with the part number.
Grundfos publishes CME curves as graphics rather than tabulated points, so the duty points on this page are the nominal figures from the technical data. For the curve itself, ask and we will send the manufacturer curve for your part number.
Why Source Grundfos CME from Watermain Supply
We Tell You When You Need The Drive
A CME earns its premium where demand swings. Where it does not, we will quote the fixed-speed CM instead and explain why — the hydraulics are identical, so the only question is how the demand behaves.
We Pick The Grade Properly
Send the water analysis. Chloride, temperature and what the system does when it sits idle decide between cast iron, 304 and 316 — and the grade also decides the pressure rating and how many stages you can have.
We Size On The Boost
Send the inlet pressure, the target pressure, the elevation and the peak flow. We size on what the pump has to add at the worst case, then let the drive handle everything lighter than that.
The Right US Build
60 Hz hydraulics, MLE motors and the voltage and phase your service actually has. Voltage is fixed per part number and there is no terminal-board changeover, so getting it right at the order is the only chance to get it right.
Engineering-Led Selection
We work from the published Grundfos curve and the limits table, and we will tell you when the seal, not the stainless grade, is what rules a liquid out.
Parts & Aftermarket
Service kits, seal kits, neck rings, motor bearing kits and wear parts identified from the pump nameplate — and we will remind you the kit is not in the box.
Frequently Asked Questions
The questions that come up most often on the phone about CME selection.
What does the E in CME actually add?
A frequency converter built into the motor terminal box. The pump end is the CM pump end and Grundfos publishes the same rated head for both to the last digit it prints, but the CME varies its own speed instead of running flat out against a throttling valve. Grundfos publishes a rated speed band per model rather than one fixed figure, from 2900 rpm at the bottom to 4000 rpm at the top, against the single fixed speed a CM turns.
Which motor is fitted to a CME?
A Grundfos MLE motor, a permanent-magnet type with the variable frequency drive incorporated, rated efficiency class IE5 to IEC 60034-30-2. The frequency converter reads built-in on every model and material Grundfos publishes for this range, so there is no external drive to specify, mount or wire.
Do I need a pressure sensor to use one?
Not to run it. Out of the box a CME holds a set speed, which is uncontrolled operation in Grundfos's terms and is what most transfer duties want. You can connect a pressure sensor to the built-in converter to get constant-pressure control, either at installation or later. If you know you want closed-loop pressure control from day one, say so when you enquire and we will confirm what the sensor adds.
What is the difference between CME-A, CME-I and CME-G?
The materials, and two things that follow from them. CME-A has a cast iron pump housing with AISI 304 internals. CME-I is AISI 304 throughout the liquid path. CME-G is AISI 316 throughout. The cast iron build is rated 145 psi maximum operating pressure and the two stainless builds are rated 232 psi, so the material also sets the pressure ceiling. Cast iron carries WRAS, ACS and NSF61 approvals where the stainless builds add UBA.
Does a CME cost less to run than a CM plus a valve?
On a swinging duty, yes, and that is the whole case for it. Throttling a fixed-speed pump wastes the energy across the valve; slowing the pump avoids making that energy in the first place. On a duty that genuinely sits at one point all day the fixed-speed CM is the better buy, because the drive is a premium you never use. Match the machine to how the demand behaves, not to which is newer.
Is the curve the pressure I get at the outlet?
No. A pump curve plots what the pump adds to the pressure already at its inlet. On a city main holding 40 psi, a pump adding 60 psi gives about 100 psi at the outlet. On a gravity-fed tank the inlet contributes almost nothing and the curve is close to what you get. Size on the boost required, not the pressure wanted.
What does the number in CME 3 or CME 10 mean?
It is Grundfos's nominal duty in cubic metres per hour, not a GPM figure. CME 3 is rated 16.4 GPM, CME 5 is 24.8 GPM and CME 10 is 52.8 GPM at 60 Hz. Pick the frame from the flow you need, then the stage count from the head. Sizing from the model number is the most common mistake on this range.
What is the difference between AQQE and AQQV seals?
The rubber, and the temperature ceiling that follows. AQQE uses EPDM and AQQV uses FKM, both with carbon against silicon carbide faces. On the stainless builds AQQE is rated to 248 °F against 194 °F for AQQV, so EPDM is the standard water seal and FKM is for mineral oils, fuels and liquids that attack EPDM. On the cast iron build both seals are 194 °F. The tallest stack in each family also falls back to 194 °F on AQQE.
Is the service kit included?
No. Grundfos lists a service kit against every CME part number, ten distinct kits across this range, and each one is a separate part number that is not supplied with the pump. Quote the pump part number when you order a kit and we will match it, because the kit follows the seal and the material as well as the frame.
What voltages are available?
200-240 V single phase, 200-240 V three phase, and 440-480 V three phase, fixed per part number on the MLE motor. There is no terminal-board changeover as on a fixed-speed CM, so a single-phase unit cannot be rewired for three-phase supply. Confirm the service before ordering.
How is CME different from CRE?
Orientation, and how far each one reaches. A CRE stands upright with its ports in line, which suits a tight floor plan under a high ceiling, and the vertical range runs to far higher heads and pressures. A CME lies horizontal on its feet with the suction on the end, which suits short headroom. Both carry an integrated drive, so the choice between them is the footprint and the duty, not the control.
Will a bigger CME give me more pressure?
It gives more flow at the same head, which is usually the real problem. If several outlets running together make the pressure sag, the system is short of flow and a larger frame fixes it. If one outlet alone is weak, head is what is missing and a taller stack in the same frame is the answer. Stepping up a frame to cure a pressure complaint is the usual mis-buy.
Ready to Size Your CME?
Send us the peak flow, the inlet pressure you can count on, the target pressure, the elevation, the liquid, how the demand behaves and the available voltage. We will respond with a sized selection, the material grade, the matching part number and lead time.
Technical data on this page is taken from Grundfos U.S. 60 Hz product literature and is subject to change by the manufacturer. Confirm against the current installation manual and pump curve before specifying.
Grundfos, CM, CME, CR, CRI, CRN, CRT, CRE, CRIE, CRNE and MLE are trademarks of Grundfos Holding A/S, used here for product identification only.
Watermain Supply is a DBA of E4 Industrial LLC, an independent industrial supplier based in Houston, Texas.
Grundfos, CM, CME, CR, CRI, CRN, CRT, CRE, CRIE, CRNE and MLE are trademarks of Grundfos Holding A/S, used here for product identification only.
Watermain Supply is a DBA of E4 Industrial LLC, an independent industrial supplier based in Houston, Texas.
- Choosing a selection results in a full page refresh.