Danfoss iSave 21 Plus, iSave 40 Data sheet

Data sheet

Energy Recovery Device

iSave 21 Plus / iSave 40

hpp.danfoss.com

Data sheet | Energy Recovery Device | iSave 21 Plus and iSave 40

Table of Contents	Contents
	1.	General information . . . . . . . . . . . . . . . . . . . . . . .	. . . . . .	. . . .	.	3
	1.1	iSave 21 Plus . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . .	. . . .	.	3
	1.2	iSave 40 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . 4
	2.	Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
	3.	Technical data . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . .	. . . .	.	5
	3.1	iSave without motor . . . . . . . . . . . . . . . . . . . . . . .	. . . . . .	. . . .	.	5
	3.2	iSave with IEC motor . . . . . . . . . . . . . . . . . . . . . . .	. . . . . .	. . . .	.	6
	3.3	iSave with NEMA motor (can only be ordered through Danfoss US)	. . . . . . . . . . . 7
	4.	Flow at different rpm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
	5.	Corrosion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
	5.1	Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
	6.	Noise level . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . .	. . .	.	. 9
	7.	Filtration . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . .	. . .	.	. 9

8. iSave drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

8.1Assembled iSave 21 Plus and iSave 40 without electric motor . . . . . . . . . . . . . .10

8.2Assembled iSave 21 Plus and iSave 40 with IEC electric motor . . . . . . . . . . . . . .12

8.3	Assembled iSave 21 Plus and iSave 40 with NEMA motor . . . . . . . . . . . . . . . . 18

9. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

10. RO systems with an iSave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

11. Performance curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

11.1Performance and torque curves iSave 21 Plus . . . . . . . . . . . . . . . . . . . . . .24

11.2	Performance and torque curves iSave 40 .		. . .	. .	. . .	. . . . . .	. .	. .		. . . . .26
12.	Service . . . . .	. . . . . . . . . . . .	. . .	. . .	. . .	. . . . . .	.	. .	.	.	.	.	.	28
12.1	Warranty . . . .	. . . . . . . . . . . .	. . .	. . .	. . .	. . . . . .	.	. .	.	.	.	.	.	28

12.2Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

12.3	Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
I

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Data sheet | Energy Recovery Device | iSave 21 Plus and iSave 40

1. General information

iSave 21 Plus

iSave 40

The iSave 21 Plus and iSave 40 consists of an isobaric pressure exchanger, a high-pressure positive displacement booster pump and an electric motor.

The isobaric pressure exchangers are based on the technology used in the Danfoss APP pumps, and the high-pressure booster pumps are based on the vane pump principle enabling a very light and compact design. The design of iSave 21 Plus and iSave 40 ensures lubrication of the moving parts by the fluid itself.

All parts included in the iSave 21 Plus and iSave 40 are designed to provide long service life with a constant high efficiency and minimum service required.

The vane pumps are fixed displacement pumps in which the flow is proportional to the number of revolutions of the driving shaft – enabling flow control.

The electric motor provides speed control of both the pressure exchanger and the high-­ pressure booster pump on the same shaft

– preventing overspin/overflushing.

The iSaves need a VFD that allows the motor to apply a constant torque from low speed to maximum speed.

The sectional drawings below illustrate the main components of the iSave 21 Plus and iSave 40, respectively

1.1 iSave 21 Plus

1.2” Victaulic connections

2.Shaft

3.Low pressure shaft seal

4.Port flange

5.Port plate

6. Valve plate

7. Cylinder drum

8. Port flange

9. Port plate

10. Pins

11. Vanes

12. Port plate

13. Coupling

14. Adapter flange

15.Rotor

16.Stator

17.Port flange

18. Outlet flange

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Data sheet | Energy Recovery Device | iSave 21 Plus and iSave 40

1.2 iSave 40

1. 3” Victaulic connections

2. Shaft

3. Low pressure shaft seal

4. Port flange

5. Port plate

6. Valve plate

7. Cylinder barrel

8. Port flange

9. Sealing plate

10. Pins

11. Vanes 12.Port plate 13. Coupling

14. Adapter flange

15. Rotor

16. Stator

17. Port plate

18. Outlet flange

2. Benefits	•	One of the smallest and lightest energy recovery
		devices on the market
	•	Few components
	•	High efficiency
	• No need for high-pressure flow meters
	• No expensive high-pressure mechanical seal
	• No risk of over spin/over flushing
	•	Easy modular service
	• All parts of the device are made of high
		corrosion-resistant materials e.g. Super Duplex

(HP) High-pressure inlet

(HP)

High-pressure outlet

(LP)		(LP)
Low-pressure inlet		Low-pressure outlet

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Data sheet | Energy Recovery Device | iSave 21 Plus and iSave 40

3.	Technical data	3.1 iSave without motor
			iSave size			iSave 21 Plus		iSave 40
			Code number			180F7015		180F7011
			Geometric displacement	cm³/rev		273		626
				In³/rev		16.7		38.2
			Pressure
			Differential pressure HP in - HP out max. 1)	bar		5		5
				psi		72.5		72.5
			HP max. outlet pressure	barg		83		83
				psig		1200		1200
			HP min. inlet pressure	barg		15		20
				psig		217		290
			HP max. inlet pressure	barg		83		83
				psig		1200		1200
			HP inlet min. pressure,	barg		3		3
			intermittent 2) 3)	psig		44		44
			LP inlet max. pressure	barg		5		5
				psig		72		72
			LP inlet max. pressure intermittent 3)	barg		10		10
				psig		145		145
			LP outlet min. pressure	barg		1		1
				psig		14.5		14.5
			LP differential LP in - out at HP max. flow	bar		0.9		1.2
				psi		13		17.5
			Speed
			Min. speed	rpm		500		600
			Max. speed	rpm		1500		1200
			Typical flow
			HP outlet flow range 4)	m³/h		6-22		21-41
			at max. differential pressure	gpm		26-96		92-180.5
			Lubrication flow at 60 barg (871 psig) max.	m³/h		0.4		0.8
				gpm		1.8		3.5
			LP inlet max. flow	m³/h		33		67
				gpm		145		295
			Torque
			Torque at max. differential pressure	Nm		49		102
			operation 1)	lbf-ft		36		75
			Max. starting torque (stick/slip)	Nm		50		150
				lbf-ft		37		110
			Media temperature 5)	oC		2-40		2-40
				oF		36-122		36-122
			Ambient temperature	oC		0-50		0-50
				oF		32-104		32-104
			Filtration requirements (nominal) 6)			3 micron melt-blow
			Salinity increase at membrane at 40% recovery rate			2-3 %
			Weight	kg		47		123
				lb		103		271
		1) Continuous torque above max. differential pressure			minutes within a period of 6 hours.
			will reduce the lifetime of the iSave.		4) Typical average flow at 60 bar.
		2) Pressure can reach this pressure level at start-up			5) Dependent on NaCI concentation.
			and permeate flush.		6) Please see section 7. filtration.
		3) Intermittent pressure is acceptable for less than 10

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Data sheet | Energy Recovery Device | iSave 21 Plus and iSave 40

3.2 iSave with IEC motor

	iSave			iSave 21 Plus A)	iSave 21 Plus	iSave 40
	Code number horizontal			180F7016	180F7017	180F7001	180F7004
	Code number vertical			180F7016	180F7017	180F7003	180F7005
	Motor size IEC version IEC 400 V,		kW	5.5	7.5	11	15
	50 Hz 1)		HP	7.5	10	15	20
	Frame size		IEC	132 S	132 M	160 L	180 L
			pole	4	4	6	6
	Motor data
	Nominal speed		rpm	1450	1450	970	970
	Min. speed at 400 V		rpm	500	2) 500	600	600
	Max. speed at 400 V		rpm	1500	1500	3) 1100	1200
	Rated current at 400 V		A	11	15.2	22	30
	Torque
	Motor torque at norminal speed	3) 4)	Nm	36	49	5) 108	146
			lbf-ft	26.5	36	80	107.7
	Motor torque at min. speed 3)		Nm	27	36	95	129
			lbf-ft	20	27	70	95
	Motor ambient temperature, max.		oC	40	40	40	40
			oF	122	122	122	122
	Motor insulation		Class	B	B	B	B
	Motor degrees of protection		IP	55	55	55	55
	Sound pressure level max. 6)		dB(A)	78	79	84	84
	Weight		kg	105	116	254	305
			lb	231	255	560	672
	Footprint (horizontal/vertical)		m²	0.31	0.32	0.5/0.16	0.54/0.17
			foot²	3.34	3.45	5.38/1.72	5.81/1.83

A)Differential pressure HP in - HP out max. is limited to 3 bar [44 psi]

1)Three-phase-asynchronous-motor according to DIN-IEC and VDE 0530 standards.

•Voltage and frequency according to IEC 38

•The motors are fitted with a rating plate in multi-tension: 380-420 V / 660-720 V, 50 Hz or 440-480 V, 60 Hz

•Tolerance ± 5% according to VDE 0530

•Standard coating according to IEC 60721-2-1

2)If voltage is below 400 V we recommend to use another size of electric motor.

Please contact Danfoss High Pressure Pumps for further information.

3)Torque load for iSave and motor see diagram on page 23 and 25.

4)Due to inertia and stick-slip friction of the iSave, the torque may exceed the maximum allowable operation torque for the iSave when it is taken into use and/ or speed is ramped up from zero to maximum. A VFD or a soft starter must be used for ramp up.

5)The starting torque must not exceed the values stated under “Max. starting torque (stick/slip)”. The VFD must be able to deliver 140% start torque. The Danfoss VFD type FC 301 and FC 302 can be used. For advice on VFD settings, please consult our relevant guideline or contact Danfoss.

6)A-weighted sound pressure level at 1 meter from the pump unit surfaces (reference box) acc. to EN ISO 20361 section 6.2. The noise measurements are performed acc. to EN ISO 3744:2010 on ERD with motor (motor-pump unit) at max. pressure and speed.

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Data sheet | Energy Recovery Device | iSave 21 Plus and iSave 40

3.3 iSave with NEMA motor (can only be ordered through Danfoss US)

iSave				iSave 21 Plus A)		iSave 21 Plus		iSave 40
Code number horizontal					180U0013	180U0052		180U0012
Code number vertical					180U0013	180U0052		180U0002
Motor size NEMA version 1)			kW		7.5	11		15
High efficiency 460 V, 60 Hz			HP		10	15		20
Frame size			NEMA		215TC	254		286TC
			pole		4	4		6
Motor data
Nominal speed			rpm		2) 1760	1765		1175
Min. speed continuous at 400 V			rpm		500	500		600
Max. speed continuous at 400 V			rpm		1500	1500		1200
Motor rated current 460 V			A		12.4	18		24.2
Torque
Motor torque at norminal speed 3) 4)			Nm		40	59.7		119
			(lbf-ft)		29.4	44		5) 88.2
Motor torque at min. speed 4)			Nm		20	31		95
			(lbf-ft)		14.7	23		70
Motor ambient temperature, max.			oC		40	40		40
3,300 feet above sea level			(oF)		122	122		122
Motor degrees of protection			IP		55	55		55
Sound pressure level max. 6)			dB(A)		78	79*)		84
Weight			kg		152	206		324
			(lb)		335	454		715
Footprint (horizontal/vertical)			m²		0.38	0.45/0.16		0.65/0.23
			foot²		4.09	4.85/1.72		7.0/2.48
A)	Differential pressure HP in - HP out max. is limited			*) Tested with IEC motor
	to 3 bar [44 psi]
1)	Three-phase-asynchronous-motor according to			5)	The starting torque must not exceed the values
	NEMA MG-1 and UL 1004-1 standards.				stated under “Max. starting torque (stick/slip)”. The
	• Insulation class F, service factor 1.25.				VFD must be able to deliver 140% start torque. The
	• Fan-cooled TEFC (IC411). Voltage and frequency				Danfoss VFD type FC 301 and FC 302 can be used.
	according to NEMA MG-1 part 12.				For advice on VFD settings, please consult our
	• The motors are fitted with a rating plate 230 /				relevant guideline or contact Danfoss.
	460 V, 60 Hz.
	• Plus or minus 10% of rated voltage, with rated			6)	A-weighted sound pressure level at 1 meter from
	frequency. Standard coating according to				the pump unit surfaces (reference box) acc. to EN
	motor supplier specifications.				ISO 20361 section 6.2. The noise measurements are
					performed acc. to EN ISO 3744:2010 on ERD with
2)	Max. speed for iSave 21 is 1500 rpm.				motor (motor-pump unit) at max. pressure and
					speed.

3)Torque load for iSave and motor see diagramme on page 23 and 25.

4)Due to inertia and stick-slip friction of the iSave, the torque may exceed the maximum allowable operation torque for the iSave when it is taken into use and/ or speed is ramped up from zero to maximum. A VFD or a soft starter must be used for ramp up.

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Data sheet | Energy Recovery Device | iSave 21 Plus and iSave 40

4.Flow at different rpm The diagram shows that the HP flow can be

changed by changing the rotation speed of the iSave. The flow/rpm ratio is constant, the required flow is obtainable by changing the rotation speed to a required value.

For accurate data please use our selection tool which is available on our website: www.isave.danfoss.com

The iSave is delivered with a 3.1 performance certificate according to EN10204.

Flow at HP out vs. rpm

	45										198
	40							iSave 40			176
	35										154
	30										132
<![if ! IE]> <![endif]>m3/h	25								iSave 21 Plus		110	<![if ! IE]> <![endif]>gpm
	20										88
	15										66
	10										44
	5										22
	0										0
	500	600	700	800	900	1000	1100	1200	1300	1400	1500
						rpm

5. Corrosion 5.1 Operation

The chart below illustrates the corrosive resistance of different types of stainless steel related to NaCl concentration and temperature. All critical parts of the iSave is made of

Super Duplex 1.4410/UNS 32 750 or Duplex 1.4462/UNS 32803.

Always flush the iSave with fresh water at operation stop in order to minimize the risk of crevice corrosion.

80º C
													Duplex
70
60
50
					316L
40
30																				Super	Duplex
20																														-
100			1000										10 000											100 000						ppmCI
160			1600										16000											160000						NaCI
																														ppm

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Data sheet | Energy Recovery Device | iSave 21 Plus and iSave 40

6. Noise level	The noise level for the iSaves is measured at max.	Pressure:
	speed, a pressure of 80 barg and a booster
	pressure of 5 bar. Since the iSave is mounted on a	• High pressure makes more noise than low
	bell housing and electric motor, the noise level	pressure.
	can only be determined for the complete unit	Mounting:
	(system).	• Rigid mounting makes more noise than
		flexible mounting due to structure-borne
	It is therefore important that a horizontal iSave	vibrations.
	unit is mounted correctly on a frame with	Connections to iSave:
	dampeners to minimize vibrations and noise.	• Pipes connected directly to the iSave make
	We recommend to mount a vertical iSave directly	more noise than flexible hoses due to
	to the floor with bolts. It is also strongly recom-	structure-borne vibrations.
	mended to use high-pressure flexible hoses	• Variable frequency drives (VFD):
	between the hard piping in the RO-plant and the	Motors regulated by VFDs can increase noise
	iSave or to use multiple connections with	level if the VFD does not have the right
	Victaulic clamps.	settings.

The noise level is influenced by:

Speed:

•High rpm makes more fluid/structure-borne pulsations/vibrations than low rpm due to higher frequency.

Noise level (dB(A) measured for the iSave 21 Plus and 40 at different speed and system pressure.

Booster pressure 3 bar.

barg/psig
	20/290	60/870	80/1160
500	60	62	68
1000	69	72	74
1500	77	78	78
iSave 21 Plus
rpm

iSave 40

barg/psig
rpm	30/435	60/870	80/1160
800	73	77	78
1000	76	79	81
1200	78	82	84

7. Filtration It is important that the incoming water is filtered properly to ensure optimum service life. A true

graded density, melt-blown depth filter cartridge rated at 3 μm is therefore recommended.

It is important with selection of a proper filter housing to ensure good cartridge end sealing. If there is a high risk of water by-pass it is recommended to use a second stage filter solution.

As the various filters on the market differ greatly, Danfoss High Pressure Pumps recommends using cartridges with consistent, reliable performance and high efficiency and where fibres are blown continuously onto a central

support core. High Pressure Pumps does not recommend cartridges requiring any type of binders or resins.

Filters can be purchased from Danfoss

High Pressure Pumps. Please see section 10.0, “RO systems with an iSave”, for installation of filter. For more information on the importance of proper filtration, please consult our publication “Filtration” (code number 521B1009), which also will provide you with an explanation of filtration definitions and a guidance on how to select the right filter.

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