Pumps - cased pumps

600 series cased pump

Arrange a demo

Overview

630 series process pumps

630 series process pumps offer four drive options, color display and intuitive menu structures that provide visual status indication and minimal key presses.

Flow rates from 0.0002 GPM to 4.76 GPM depending on model and pumphead/tubing options.

Pumphead options available as standard (others available on request):

620R pumphead for continuous tubing
620RE and 620RE4 pumpheads for tube elements
620L and 620LG twin channel low pulse pumpheads

Features and benefits

Color display and intuitive menu structures provide visual status indication and minimal key presses
Flow rates from 0.001 L/min (0.0002 USGPM) to 18 L/min (4.76 USGPM) depending on model and pumphead/tubing options
620R, 620RE, 620RE4, 620L and 620LG pumpheads available
2,650:1 speed control range from 0.1 rpm to 265 rpm in 0.1 rpm increments
Keypad incorporates 3-level security PIN lock
IP31 (NEMA 2) and IP66 (NEMA 4X) cased pumps available
Dual voltage, 115 V/230 V 50/60 Hz
Remote Analogue/Digital, RS232, RS485, PROFIBUS®, PROFINET®, SCADA and EtherNet/IP™ control options

Technical summary

Max. flow rate	18 L/min
Min. flow rate	0.001 L/min
Max. flow rate	301 USGPH
Min. flow rate	0.02 USGPH
Drive speed control ratio	2650:1
Operating temperature range	5 to 40 °C
Operating temperature range	41 to 104 °F
Control types	EtherNet/IP™, PROFIBUS®, PROFINET®, Remote Analogue/Digital, RS232, RS485, SCADA
Standards	CE, cETLus, C-Tick, IRAM, NSF/ANSI 61 (for Marprene tubing and loadsure elements)
Drive ingress protection	IP31, IP66, NEMA 2, NEMA 4X
Drive power supply	100 to 120 V/200 to 240 V 1ph 50/60 Hz 250 VA, 100 V to 120 V/200 V to 240 V 1ph 50/60 Hz 250 VA
Compatible tubing bore size	6.4, 8, 9.6, 12, 12.7, 15.9, 16, 17 mm

Technical Summary table lists features available within the range. See ‘Technical specifications’ tab for model specific information.

Performance

630 Drive with 620R Pumphead performance

620R twin-roller pumpheads for continuous 3.2 mm wall thickness tubing — Tube bore and flow rates — L/min (USGPH)
Tube material	Speed	6.4mm	9.6mm	12.7mm	15.9mm
Marprene® TL, Bioprene® TL	0.1-265rpm	0.001–3.4 (0.02– 53.9)	0.003–6.6 (0.05– 105)	0.004–11 (0.06– 174)	0.005–12 (0.08– 190)
Pumpsil®	0.1-265rpm	0.001–3.2 (0.02– 50.7)	0.003–6.9 (0.05– 109)	0.004–11 (0.06– 174)	0.01–15 (0.16– 238)
GORE® STA-PURE® Pump Tubing – Series PFL	0.1-265rpm	0.001–3.2 (0.02– 50.7)	0.003–6.6 (0.05– 105)	0.004–11 (0.06– 174)	0.006–16 (0.1– 254)
PureWeld® XL	0.1-265rpm	NA	0.01–6.7 (0.16– 106)	0.02–11 (0.32– 174)	0.03–18 (0.43– 285)

630 Drive with 620RE Pumphead performance

620RE two-roller low-pulse pumpheads for LoadSure elements — Tube bore and flow rates — L/min (USGPH)
Tube material	Speed	12mm	17mm
Marprene® TM, Bioprene® TM	0.1-265rpm	0.004–9.8 (0.06– 155)	0.01–16 (0.16– 254)
Marprene® TL, Bioprene® TL	0.1-265rpm	0.004–11 (0.06– 174)	0.01–18 (0.16– 285)
Pumpsil®	0.1-265rpm	0.004–10 (0.06– 159)	0.01–16 (0.16– 254)
GORE® STA-PURE® Pump Tubing – Series PFL	0.1-265rpm	0.004–11 (0.06– 174)	0.01–19 (0.16– 301)

630 Drive with 620RE4 Pumphead performance

620RE4 four-roller low-pulse pumpheads for LoadSure elements — Tube bore and flow rates — L/min (USGPH)
Tube material	Speed	12mm	17mm
Marprene® TM, Bioprene® TM	0.1-265rpm	0.003–8.3 (0.05–132)	0.004–11 (0.06–174)
Marprene® TL, Bioprene® TL	0.1-265rpm	0.003–8.3 (0.05–132)	0.005–12 (0.08–190)
Pumpsil®	0.1-265rpm	0.003–8.7 (0.05–138)	0.004–11 (0.06–174)
GORE® STA-PURE® Pump Tubing – Series PFL	0.1-265rpm	0.003–9 (0.05–143)	0.005–13 (0.08–206)

630 Drive with 620L Pumphead performance

620L twin-channel low-pulse pumpheads for LoadSure elements — Tube bore and flow rates — L/ min (USGPH)
Tube material	Speed	Y element tubing			Continuous tubing (flow per channel - max of 2 channels)
Tube material	Speed	8.0mm	12.0mm	16.0mm	8.0mm	12.0mm	16.0mm
Pumpsil®	0.1-265rpm	0.002–4.4 (0.03–69.7)	0.003–8.5 (0.05–135)	0.005–11.5 (0.08–182)	0.001–2.2 (0.02–34.9)	0.002–4.3 (0.03–68.2)	0.003–5.8 (0.05–91.9)
Marprene® , Bioprene®	0.1-265rpm	0.002–4.5 (0.03–71.3)	0.003–8.0 (0.05–127)	0.005–11.3 (0.08–179)	0.001–2.3 (0.02–36.5)	0.002–4.0 (0.03–63.4)	0.003–5.7 (0.05–90.3)
GORE® STA-PURE® Pump Tubing Series PFL, GORE® STA-PURE® Pump Tubing Series PCS (620LG pumphead only)	0.1-265rpm	0.002–5.2 (0.03–82.4)	0.003–9.0 (0.05–143)	0.005–12.4 (0.08–197)	0.001–2.6 (0.02–41.2)	0.002–4.5 (0.03–71.3)	0.003–6.7 (0.05–106)

630 Drive with 620LG Pumphead performance

620LG twin-channel low-pulse pumpheads for GORE® STA-PURE LoadSure elements — Tube bore and flow rates — L/ min (USGPH)
Tube material	Speed	Y element tubing			Continuous tubing (flow per channel - max of 2 channels)
Tube material	Speed	8.0mm	12.0mm	16.0mm	8.0mm	12.0mm	16.0mm
GORE® STA-PURE® Pump Tubing Series PFL, GORE® STA-PURE® Pump Tubing Series PCS (620LG pumphead only)	0.1-265rpm	0.002–5.2 (0.03–82.4)	0.003–9.0 (0.05–143)	0.005–12.4 (0.08–197)	0.001–2.6 (0.02–41.2)	0.002–4.5 (0.03–71.3)	0.003–6.7 (0.05–106)

Specifications

Technical specifications

	630 Drive with 620R Pumphead	630 Drive with 620RE Pumphead	630 Drive with 620RE4 Pumphead	630 Drive with 620L Pumphead	630 Drive with 620LG Pumphead
Pumphead number of rollers	2	2	4
Pumphead number of channels	1	1	1	2	2
	0.001 L/min to 18	0.004 L/min to 18	0.003 L/min to 13	0.002 L/min to 13.3	0.002 L/min to 13.3
	0.02 USGPH to 285	0.06 USGPH to 301	0.05 USGPH to 206	0.03 USGPH to 211	0.03 USGPH to 211
	0.0002 USGPM to 4.76	0.0002 USGPM to 4.76	0.0002 USGPM to 4.76	0.0002 USGPM to 4.76	0.0002 USGPM to 4.76
Drive speed control ratio	2650:1	2650:1	2650:1	2650:1	2650:1
Drive speed	0.1 - 265 rpm	0.1 - 265 rpm	0.1 - 265 rpm	0.1 - 265 rpm	0.1 - 265 rpm
Operating temperature range	5 to 40 °C	5 to 40 °C	5 to 40 °C	5 to 40 °C	5 to 40 °C
Operating temperature range	41 to 104 °F	41 to 104 °F	41 to 104 °F	41 to 104 °F	41 to 104 °F
Weight	19.6 - 20.5 kg	19.6 - 20.5 kg	20.1 - 21 kg	24.3 - 25.2 kg	24.3 - 25.2 kg
Weight	43.2 - 45.2 lbs	43.2 - 45.2 lbs	44.3 - 46.3 lbs	53.6 - 55.6 lbs	53.6 - 55.6 lbs
Drive weight	16.5, 17.4 kg	16.5, 17.4 kg	16.5, 17.4 kg	16.5, 17.4 kg	16.5, 17.4 kg
Drive weight	36.4, 38.5 lbs	36.4, 38.5 lbs	36.4, 38.5 lbs	36.4, 38.5 lbs	36.4, 38.5 lbs
NEMA module weight	0.9 kg	0.9 kg	0.9 kg	0.9 kg	0.9 kg
NEMA module weight	2 lbs	2 lbs	2 lbs	2 lbs	2 lbs
Control types	EtherNet/IP™, PROFIBUS®, PROFINET®, Remote Analogue/Digital, RS232, RS485, SCADA	EtherNet/IP™, PROFIBUS®, PROFINET®, Remote Analogue/Digital, RS232, RS485, SCADA	EtherNet/IP™, PROFIBUS®, PROFINET®, Remote Analogue/Digital, RS232, RS485, SCADA	EtherNet/IP™, PROFIBUS®, PROFINET®, Remote Analogue/Digital, RS232, RS485, SCADA	EtherNet/IP™, PROFIBUS®, PROFINET®, Remote Analogue/Digital, RS232, RS485, SCADA
Drive control options	Bp, BpN, Du, DuN, DuS, En, EnN, Pn, PnN, S, SN, U, UN, US	Bp, BpN, Du, DuN, DuS, En, EnN, Pn, PnN, S, SN, U, UN, US	Bp, BpN, Du, DuN, DuS, En, EnN, Pn, PnN, S, SN, U, UN, US	Bp, BpN, Du, DuN, En, EnN, Pn, PnN	Bp, BpN, Du, DuN, En, EnN, Pn, PnN
Standards	CE, cETLus, C-Tick, IRAM, NSF/ANSI 61 (for Marprene tubing and loadsure elements)	CE, cETLus, C-Tick, IRAM, NSF/ANSI 61 (for Marprene tubing and loadsure elements)	CE, cETLus, C-Tick, IRAM, NSF/ANSI 61 (for Marprene tubing and loadsure elements)	CE, cETLus, C-Tick, IRAM, NSF/ANSI 61 (for Marprene tubing and loadsure elements)	CE, cETLus, C-Tick, IRAM, NSF/ANSI 61 (for Marprene tubing and loadsure elements)
Drive ingress protection	IP31, IP66, NEMA 2, NEMA 4X	IP31, IP66, NEMA 2, NEMA 4X	IP31, IP66, NEMA 2, NEMA 4X	IP31, IP66, NEMA 2, NEMA 4X	IP31, IP66, NEMA 2, NEMA 4X
Drive humidity	(Non-condensing) 80% up to 31°C (88°F), decreasing linearly to 50% at 40C (104F)	(Non-condensing) 80% up to 31°C (88°F), decreasing linearly to 50% at 40C (104F)	(Non-condensing) 80% up to 31°C (88°F), decreasing linearly to 50% at 40C (104F)	(Non-condensing) 80% up to 31°C (88°F), decreasing linearly to 50% at 40C (104F)	(Non-condensing) 80% up to 31°C (88°F), decreasing linearly to 50% at 40C (104F)
Drive noise	<70dB(A) at 1m	<70dB(A) at 1m	<70dB(A) at 1m	<70dB(A) at 1m	<70dB(A) at 1m
Max. altitude	2000 m	2000 m	2000 m	2000 m	2000 m
Drive power supply	100 to 120 V/200 to 240 V 1ph 50/60 Hz 250 VA, 100 V to 120 V/200 V to 240 V 1ph 50/60 Hz 250 VA	100 to 120 V/200 to 240 V 1ph 50/60 Hz 250 VA, 100 V to 120 V/200 V to 240 V 1ph 50/60 Hz 250 VA	100 to 120 V/200 to 240 V 1ph 50/60 Hz 250 VA, 100 V to 120 V/200 V to 240 V 1ph 50/60 Hz 250 VA	100 to 120 V/200 to 240 V 1ph 50/60 Hz 250 VA, 100 V to 120 V/200 V to 240 V 1ph 50/60 Hz 250 VA	100 to 120 V/200 to 240 V 1ph 50/60 Hz 250 VA, 100 V to 120 V/200 V to 240 V 1ph 50/60 Hz 250 VA
Compatible tubing bore size	6.4, 9.6, 12.7, 15.9 mm	12, 17 mm	12, 17 mm	8, 12, 16 mm	8, 12, 16 mm

630 Drive with 620R Pumphead dimensions

630 Drive with 620RE Pumphead dimensions

630 Drive with 620RE4 Pumphead dimensions

630 Drive with 620L Pumphead dimensions

630 Drive with 620LG Pumphead dimensions

Materials of construction

Bearings	Carbon steel
Driveshaft	Stainless steel 440C
Drive casework	Pressure die-cast aluminum LM24, Pressure die-cast aluminum LM6
Drive casework coating	Exterior grade polyester powder coat
Guide roller assembly	MoS2 filled Nylon 6 (Nylatron), Stainless steel 303, Stainless steel 316
Drive keypad/HMI	Polyester
Pumphead front back plates	Aluminum alloy HS30
Drive rear blanking plate	Stainless steel 316
Pumphead body assembly	Alocrom pre-treatment, Aluminum alloy NS4 anodized, Exterior grade polyester powder coat, Polyester epoxy powder, Powder coated aluminum LM24, Pressure die-cast aluminum LM24
Pumphead guard	Alocrom pre-treatment, Exterior grade polyester powder coat, Pressure die-cast aluminum LM24
Pumphead roller assembly	Fortron 1140L4 (PPS), MoS2 filled Nylon 6 (Nylatron), Stainless steel 303, Stainless steel 316
Pumphead rotor assembly	Aluminum alloy HE30, Dupont Hytrel G5544, Fortron 1140L4 (PPS)
Pumphead track	Aluminum alloy NS4 anodized, Powder coated aluminum LM24
Spindles	Stainless steel 303S31
Switch-plate	ABS PA-765
Tube clamp assembly	Aluminum alloy HE30, Polypropylene

Information listed covers the complete range. For detailed specifications of individual models/components refer to user manual or contact WMFTS representative.

Control

Control options

Key to pump drive models
630S	630SN	630U	630UN	630Du	630DuN	630Bp	630BpN	630US	630DuS	630En	630EnN	630Pn	630PnN
Standard	Standard IP66 / NEMA 4X	Universal	Universal IP66 / NEMA 4X	Digital Universal	Digital Universal IP66 / NEMA 4X	Bus Pump / Profibus	Bus Pump / Profibus IP66 / NEMA 4X	Universal SCADA / IP66 / NEMA 4X	Digital Universal SCADA / IP66 / NEMA 4X	EtherNet/IP	EtherNet/ IP / IP66 / NEMA 4X	PROFINET®	PROFINET® / IP66 / NEMA 4X

Manual control
Pump drive	630S	630SN	630U	630UN	630Du	630DuN	630Bp	630BpN	630US	630DuS	630En	630EnN	630Pn	630PnN
Intuitive keypad and colour display	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔
Choice of flowrate or speed display	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔
Full calibration with choice of flow units	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔
MemoDose function	✔	✔	✔	✔	✔	✔			✔	✔
Auto restart facility	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔
Guard switch detection	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔
Leak detection			✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔
Dipensing (Network Control)											✔	✔	✔	✔

Remote control
Pump drives	630S	630SN	630U	630UN	630Du	630DuN	630Bp	630BpN	630US	630DuS	630En	630EnN	630Pn	630PnN
Configurable Start/Stop, leak detector and pressure switch input via contact closure or 5 V TTL or 24 V industrial logic			✔	✔	✔	✔					✔	✔	✔	✔
Configurable Start/Stop, leak detector and pressure switch input via 110 V industrial logic									✔	✔
Direction change and auto/manual toggle input via contact closure or 5 V TTL or 24 V industrial logic			✔	✔	✔	✔
Direction change and auto/manual toggle input via 110 V industrial logic									✔	✔
Remote operation of MemoDose (foot/hand‑switch or logic input)			✔	✔	✔	✔
Four configurable digital status outputs through 24 V, 30 W relays				✔		✔
Four configurable digital status outputs through 110 V relays									✔	✔
Menu configurable logic outputs			✔		✔
Remote pressure/flow sensors											✔	✔	✔	✔

Analogue speed control
Pump drives	630S	630SN	630U	630UN	630Du	630DuN	630Bp	630BpN	630US	630DuS	630En	630EnN	630Pn	630PnN
Fully configurable inputs; 0-10 V or 4-20 mA			✔	✔	✔	✔			✔	✔
Analogue outputs; 0-10 V, 4-20 mA			✔	✔	✔	✔			✔	✔
Keypad/analogue input scaling (replacement of diaphragm pumps)					✔	✔				✔
Tacho frequency output; 0-1478 Hz			✔	✔	✔	✔
2x sensor inputs 4-20 mA*											✔	✔	✔	✔

Security
Pump drives	630S	630SN	630U	630UN	630Du	630DuN	630Bp	630BpN	630US	630DuS	630En	630EnN	630Pn	630PnN
3-level Security PIN lock	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔	✔

Network communication
Pump drives	630S	630SN	630U	630UN	630Du	630DuN	630Bp	630BpN	630US	630DuS	630En	630EnN	630Pn	630PnN
RS485 network control						✔				✔
RS232 network control					✔

Digital pump commands (Profibus / EtherNet/IP)
Pump drives	630S	630SN	630U	630UN	630Du	630DuN	630Bp	630BpN	630US	630DuS	630En	630EnN	630Pn	630PnN
PROFIBUS® DP V0							✔	✔
PROFINET® (CC-B & Netload Class III)													✔	✔
EtherNet/IP™											✔	✔
Communication speeds from 9.6 kbits/s up to 12000 kbits/s							✔	✔
Network speed: 10/100 Mbps - Full Duplex Operation											✔	✔
Network speed: 100 Mbps - Full Duplex Operation													✔	✔
Auto-detect bus speed							✔	✔
Speed set point							✔	✔			✔	✔	✔	✔
Speed feedback							✔	✔			✔	✔	✔	✔
Flow calibration function							✔	✔			✔	✔	✔	✔
Hours run							✔	✔			✔	✔	✔	✔
Revolution counter							✔	✔			✔	✔	✔	✔
Leak detection							✔	✔			✔	✔	✔	✔
Low fluid level alarm							✔	✔			✔	✔	✔	✔
Diagnostic feedback							✔	✔			✔	✔	✔	✔
Flow Totaliser											✔	✔	✔	✔
Sensor scaling											✔	✔	✔	✔
Dispensing (Network Control)**											✔	✔	✔	✔

*Range of 3rd party pressure/flow sensors supported—see compatible sensor list on www.wmftg.com/literature

**Dispensing (Network/Manual) - Store up to 100 recipes locally or via network control. Features include volume, flow rate, anti-drip, ramp and time delays. Run these as batches using local, network or manual keypad control.

Literature

Brochures

Industrial EtherNet flyer (US).pdf
PDF - 313.6kb
Water and wastewater industry (US).pdf
PDF - 531.2kb

Datasheet

630 Drive with 620RE4 pumphead datasheet (US).pdf
PDF - 814.2kb
630 Drive with 620R pumphead datasheet (US).pdf
PDF - 828kb
630 Drive with 620LG pumphead datasheet (US).pdf
PDF - 793.8kb
630 Drive with 620RE pumphead datasheet (US).pdf
PDF - 816kb
630 Drive with 620L pumphead datasheet (US).pdf
PDF - 794.5kb

Manuals

630 Pn-PnN manual (EN).pdf
PDF - 3.9mb
630 S-SN manual (EN).pdf
PDF - 3mb
630 Bp-BpN manual (EN).pdf
PDF - 3mb
630 Bp-BpN manual (EN).pdf
PDF - 3mb
630 En-EnN manual (EN).pdf
PDF - 4mb
630 U-UN manual (EN).pdf
PDF - 4.7mb
630 Du-DuN manual (EN).pdf
PDF - 4.7mb

Other Resources

Watson-Marlow 530, 630, 730 EtherNet-IP™ and PROFINET® compatible sensor list (EN).pdf
PDF - 235.2kb
530 630 730 Pn PnN GSDML compatibility guide.pdf
PDF - 43.5kb
530 630 730 En EnN EDS compatibility guide (EN).pdf
PDF - 44.7kb

530-630-730-EtherNetIP-pump-rev-2.5.eds
EDS - 113.9kb

gsdml-v2.4-watson-marlow-530-630-730-profinet-pump-20230316.zip
ZIP - 5.6kb
Engineering Specifications 630 (US).zip
ZIP - 1.5mb

Pumpheads

620RE LoadSure tube element pumphead

620RE is a high-performance, accurate, two-roller pumphead with LoadSure rapid tube element change technology
4mm wall elements in 12mm or 17mm bore sizes allow pressures up to 4bar and flow rates up to 18 liter/min
Elements are available with Tri-clamp sanitary fittings; and with Cam and Groove fittings

620RE4 LoadSure tube element pumphead

620RE4 is a high-performance, accurate, four-roller pumphead with LoadSure rapid tube element change technology
4mm wall elements in 12mm or 17mm bore sizes allow pressures up to 4bar and flow rates up to 13 liter/min with minimized pulsation
Elements are available with industry-standard tri-clamp sanitary fittings; and with Cam and Groove fittings for industry

620R continuous tubing pumphead

620R pumphead accommodates 3.2mm wall continuous tubing in four bore sizes from 6.4mm to 15.9mm, giving up to 16 liter/min flow at up to 2bar pressure
Tubing is available in eight materials for almost any chemical requirement

620L low pulsation pumphead

620L is a specialist 2bar, six-roller pumphead designed for accurate dispensing to ±0.5%. Minimal pulsation is achieved by splitting the inlet flow into two tubes passing over twin, offset tracks. The two sets of out-of-phase pulses cancel each other out when the channels merge
Uses 4.0mm wall Y-elements in a choice of six materials
Two single channels are also available
Tubing choices: 8mm, 12mm, and 16mm bore, offering flow rates from 0.002 to 12.4 liter/min
Dispenses 500ml in 3.5 seconds

Drives

Simple-to use HMI requiring minimal key presses to reduce chances of costly errors. Flow proportional to pump speed over 2,650:1 control range. IP31 wipedown pumps and IP66 cased pumps for washdown environments.

630S - IP31 and 630SN - IP66 are simple, plug-in and switch on pumps offering economy of ownership. Ultimate process security with a 3 level PIN lock.
630U - IP31 and 630UN - IP66 with all the features of the S/SN models, plus configurable inputs and outputs.
630Du - IP31 and 630DuN - IP66 with configurable inputs and outputs, plus RS232 and RS485.
630Bp - IP31 and 630BpN - IP66 with real time communication makes your process secure and flexible. Bus speed 9.6 kbits/s up to 12000 kbits/s connectivity
630En - IP31 and 630EnN - IP66 EtherNet/IP connectivity for fast and easy access to pump data over Industrial Ethernet
630Pn - IP31 and 630PnN - IP66 PROFINET connectivity for fast and easy access to pump data over Industrial Ethernet

Order Information

Product codes

A	B	C	D
Model	Ingress Protection	Pumphead	Plug options
3: S	1: IP31/ NEMA 2	02: 620R³	U: UK mains plug
4: U	N: IP66/ NEMA 4X	E2: 620RE³	E: EU mains plug
5: Du	S: SCADA IP66/ NEMA 4X^1,2	E4:620RE4³	A: American mains plug
6: Bp		5L: 620L	K: Australia mains plug
8: En		5G: 620LG	R: Argentina mains plug
9: Pn			C: Swiss mains plug
			D: India/ South Africa mains plug
			B: Brazilian mains plug

Notes: 1. U and Du models only 2. Only available with American mains plug 3. Not available for US or DuS models