Taco SKV SelfSensing User manual

© 2017Taco, Inc. 1
Installation, Operation, and Maintenance Manual
302-365
SKV SelfSensing
Vertical In-line Pump
SUPERSEDES: January 14, 2014 EFFECTIVE: June 5, 2017
Plant ID: 001-4208
Table of Contents
1 SAFETY REQUIREMENTS. . . . . . . . . . . . . . . . . . . . 2
2 GENERAL INSTALLATION REQUIREMENTS. . . . . 2
2.1 Receiving Pump. . . . . . . . . . . . . . . . . . . . . . . . . 2
2.2 Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.3 Foundation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
3 MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
3.1 Routine Inspections . . . . . . . . . . . . . . . . . . . . . . 2
3.2 Close Coupled Pumps . . . . . . . . . . . . . . . . . . . . 3
3.3 Close Coupled Motors . . . . . . . . . . . . . . . . . . . . 3
3.4 Mechanical Seal. . . . . . . . . . . . . . . . . . . . . . . . . 3
4 DIS-ASSEMBLY AND RE-ASSEMBLY. . . . . . . . . . . 3
4.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4.2 Dis-Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4.3 Re-Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
5 PUMP PIPING - GENERAL. . . . . . . . . . . . . . . . . . . . 4
6 APPLICATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
7 MECHANICAL INSTALLATION . . . . . . . . . . . . . . . . 4
7.1 Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
7.2 VFD Mounting to Pump . . . . . . . . . . . . . . . . . . . 4
7.3 VFD Mounting to Wall . . . . . . . . . . . . . . . . . . . . 6
7.4 Pump Piping – Detailed . . . . . . . . . . . . . . . . . . . 6
8 ELECTRICAL CONNECTIONS. . . . . . . . . . . . . . . . . 9
8.1 Exploded Views . . . . . . . . . . . . . . . . . . . . . . . . . 9
8.2 Electrical Installation . . . . . . . . . . . . . . . . . . . . 10
8.3 Grounding Requirements. . . . . . . . . . . . . . . . . 12
8.4 Typical Terminal Wiring Configurations . . . . . . 18
9 USER INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . 28
9.1 Local Control Panel . . . . . . . . . . . . . . . . . . . . . 28
9.2 Backup and Copying Parameter Settings . . . . 30
9.3 Password Protection . . . . . . . . . . . . . . . . . . . . 31
10 PUMP CONTROL SET-UPS . . . . . . . . . . . . . . . . . 34
10.1 SelfSensing Description. . . . . . . . . . . . . . . . . 34
10.2 Set-up Menu . . . . . . . . . . . . . . . . . . . . . . . . . 34
10.3 Variable Flow Control (Flow Compensation) . 35
10.4 Constant Flow Control . . . . . . . . . . . . . . . . . . 35
10.5 Constant Pressure Control. . . . . . . . . . . . . . . 36
10.6 Sequencing (Standby Pump Alternation). . . . 36
11 START-UP PROCEDURE . . . . . . . . . . . . . . . . . . 37
11.1 Check Points Before First Start . . . . . . . . . . . 37
11.2 Check Motor Rotation . . . . . . . . . . . . . . . . . . 37
11.3 Start Pump. . . . . . . . . . . . . . . . . . . . . . . . . . . 37
11.4 Verify Flow. . . . . . . . . . . . . . . . . . . . . . . . . . . 38
12 SYSTEM BALANCING . . . . . . . . . . . . . . . . . . . . . 39
12.1 About SelfSensing ProBalance . . . . . . . . . . . 39
12.2 My Personal Menu for ProBalance . . . . . . . . 40
12.3 Balancing Procedure . . . . . . . . . . . . . . . . . . . 41
12.4 Additional Settings. . . . . . . . . . . . . . . . . . . . . 49
13 MENUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
14 WARNINGS AND ALARMS . . . . . . . . . . . . . . . . . 61
14.1 Supplemental Warning and Alarm Settings . . 70
15 CASING/IMPELLER WEAR RING CLEARANCES 73
16 SKS PUMP PROBLEM ANALYSIS . . . . . . . . . . . 74
17 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . 75
17.1 Power-dependent Specifications . . . . . . . . . . 75
17.2 Connection Tightening Torques. . . . . . . . . . . 77
A SET-UP FOR STANDBY PUMP ALTERNATION . 78
B ON-SITE DRIVE MOUNTING TO WALL OR PUMP 83

Taco® SKV
2 302-365, Effective: June 5, 2017
© 2017 Taco, Inc.
1 SAFETY REQUIREMENTS
CAUTION: These instructions should be
read completely prior to installation of the
equipment. A copy of these instructions
should be retained on file for future refer-
ence.
WARNING: Electrical shock hazard. Discon-
nect ALL power sources when installing or
servicing this equipment to prevent electrical
shock or equipment damage.
This pump is intended for the circulation of water or other
suitable HVAC media. It is not intended for hazardous,
corrosive, or flammable liquids.
Pump must not be operated until all piping and/or electri-
cal connections are in place.
Proper care and suitable equipment should be used to
move and install this heavy equipment.
Care should be taken when installing pipe systems to
avoid placing an excessive load on the pump unions.
Refer to motor installation instructions to determine
proper terminal connections in order to obtain correct
pump rotation.
When the system piping is used as an earth bonding path
for the building electrical services (check local codes),
the pump should not be relied upon as part of the circuit.
A properly installed bridging connection should be pro-
vided.
If electrical connection is to be made using any means
other than rigid conduit, proper strain relief must be pro-
vided (min 100N tension).
Pump should be installed according to local electrical and
safety codes using appropriate size wire and suitable
over current protection. It should use a lockable isolator
or circuit breaker conforming to applicable electrical
codes.
It is recommended that the pump be fitted with a suitable
“emergency stop” per the requirements of applicable
electrical codes.
2 GENERAL INSTALLATION
REQUIREMENTS
2.1 Receiving Pump
Inspect for shipping damage. If a shortage or damage
occurs, contact carrier immediately.
2.2 Location
Install vertically with motor up. Consult factory for hori-
zontal mounting.
Pump should be accessible for inspection and repair
work, head room must be provided for the use of hoist or
tackle as necessary.
Lift pump by slinging through motor eye bolts and secur-
ing through pump adapter.
NOTE: In no case should any part of motor
be covered with insulation.
2.3 Foundation
The pump must always be supported.
Pumps with smaller motors may be suspended in the pip-
ing, provided the piping is supported adjacent to the
pump.
For pumps with larger motors, the pump should be
attached to a support utilizing the tapped hole or holes in
the bottom of the pump casing.
NOTE: Piping loads shall not be applied to
the pump.
Pump must be allowed to move with piping movement.
Expansion of piping must be taken into account
when piping and suitable devices should be employed.
NOTE: Provide vibration isolation pads
under floor mounted supports. Do not sup-
port unit by the motor eye-bolts.
3 MAINTENANCE
3.1 Routine Inspections
Routine inspections should be made on a regular basis.
Inspections made while pump is running should reveal
potential failures.
• Inspect motor bearings for any sign of temperature
rise. Temperature should not exceed 160°F. Temper-
ature rise may indicate the early stages of bearing
problems.
• Listen for any unusual noise:
1.Air trapped in pump.
2.Hydraulic noise.
3.Mechanical noise in motor and/or pump.
• Check suction gauge reading and confirm that it is
normal.
NOTE: The pump should not be rigidly attached to the
mmmmbase/pad structure unless flexible couplings are used.

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• Check discharge gauge reading and confirm that it is
normal. If gauge readings are abnormal find out why.
NOTE: Suction and discharge gauges
should read the same with pump stopped.
3.2 Close Coupled Pumps
The pump section is attached directly to the motor shaft
and does not contain bearings.
3.3 Close Coupled Motors
The motor must be lubricated in accordance with the
manufacturer’s recommendations. Do not over lubricate
the motor bearings as this could cause premature bear-
ing failure.
3.4 Mechanical Seal
The mechanical seal is the “John Crane” Type 21 Gen-
eral Purpose Seal for the 175 psig pressure rating.
A “John Crane” Type 2 General Purpose Seal is used for
the 300 psig pressure rating.
4 DIS-ASSEMBLY AND RE-
ASSEMBLY
4.1 General
If the pump has been maintained and serviced properly,
breakdowns requiring pump disassembly should occur
only rarely.
• If a problem occurs, the cause should be determined,
if possible, before dis-assembling. (See “Problem
Analysis”)
• If the pump is being dis-assembled, all parts must be
carefully handled, avoid heavy blows and shocks.
• All parts must be carefully cleaned and inspected for
wear. Recondition or replace parts where necessary.
4.2 Dis-Assembly
Drain liquid from casing by removing drain plug.
CAUTION: Allow pump to cool and secure
suction and discharge valves before working
on pump!
Remove re-circulation line.
Remove bolts holding cover/adapter to casing, pry cover/
adapter and motor assembly from casing.
302-365, Effective: June 5, 2017
© 2017 Taco, Inc.
Remove impeller bolt in a counterclockwise direction.
Remove impeller and key.
In all cases of mechanical seal arrangement, after
removing the sleeve and its seal assembly, the seal rotat-
ing element may be drawn off the shaft sleeve.
NOTE: Apply silicone grease on the OD of
the sleeve in the area between the seal and
the end of the sleeve. This will help removal
of the old seal. The stationary element is to
be removed from the cover.
All parts must be cleaned and inspected for wear.
Replace parts where necessary.
4.3 Re-Assembly
Be certain that all parts to be replaced are free from
burrs, with screw threads and connecting faces clear and
free from damage.
Insert stationary element of seal into cover adapter, slip
cover-adapter over shaft and engage rabbit of motor.
Note: Do not touch the seal surfaces
because this may result in leakage. Do not
contaminate seal faces with fingerprints.
Lubricate smaller OD of shaft sleeve with silicone grease.
Do not use petroleum oil or grease.
Place spring on shaft sleeve to abut against sleeve
shoulder. Slide rotary seal on sleeve until it contacts
spring.
Slide the shaft sleeve on the shaft, larger bore first. Be
certain the O-ring is correctly seated in the groove.
Assemble impeller key and impeller on shaft. Refit with
new impeller washer on impeller bolt and tighten care-
fully. Be certain that the impeller rotates freely by hand.
Apply a few spots of gasket adhesive to gasket surface of
cover. Place a new casing gasket against gasket surface
and press against adhesive.
Assemble cover-adapter complete with motor into cas-
ing. Insure that gasket is seated correctly. Install hex-
headed cap screws into casing tapings and tighten uni-
formly.
Reconnect re-circulation line and drain plug.

Taco® SKV
4 302-365, Effective: June 5, 2017
© 2017 Taco, Inc.
5 PUMP PIPING - GENERAL
CAUTION: NEVER connect any pump to
piping, unless extra care is taken to measure
and align the piping flanges well. Always
start piping from pump. Use as few bends as
possible and preferably long radius elbows.
Do not use flexible connectors on the suction or dis-
charge of a vertical in-line pump, unless the pump is rig-
idly mounted to a foundation. Ensure piping exerts no
strain on pump as this could distort the casing causing
breakage or early failure due to pump misalignment. All
connecting pipe flanges must be square to the pipe work
and parallel to the pump flanges.
Suction and discharge pipes may be increased or
decreased at pump nozzle to suit pump capacity and par-
ticular conditions of installation. Use eccentric reducers
on suction connection with flat side uppermost.
Lay out the suction line with a continual rise towards the
pump without high points, thus eliminating possibility of
air pockets that may prevent the pump from operating
effectively.
6 APPLICATION
7 MECHANICAL INSTALLATION
7.1 Location
In open systems, locate the unit as close as practical to
the liquid supply source, with a short, direct suction pipe.
Ensure adequate space is left above and around the unit
for operation, maintenance, service and inspection of
parts.
In closed systems, where possible, the pumps should be
installed immediately downstream of the expansion tank/
make-up connection. This is the point of zero pressure
change and is necessary for effective pump operation.
Do not install more than one expansion tank connection
into any closed hydronic system.
Electric motor driven pumps should not be located in
damp or dusty location without special protection.
Airflow into the motor and/or motor fan should not be
obstructed.
7.2 VFD Mounting to Pump
For instructions on mounting the VFD directly to the
pump, see the diagrams and notes on the following page.
Working Pressure: 175 psig
Optional Working Pressure: 300 psig
Temperature: 250°F Standard
300°F Hi Temperature

Taco® SKV
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Figure 7-1: VFD Mounting to Pump
ALTERNATIVE BRACKET VIEW
SKV or SKS BOM Assembly
ITEM # DESCRIPTION QTY
1 VFD 1
2 BAR BRACKET 2
3 WIRE HARNESS - MOTOR POWER 1
4 VIBRATION ISOLATION MOUNT 4
5 SAFETY STRAP 4
6 NUT (VFD) 4
7 LOCK WASHER (VFD) 4
8 WASHER (VFD) 4
9 SCREW (MOTOR) 4
10 LOCK WASHER (MOTOR) 4
11 WASHER (MOTOR) 4
N/A "LOCTITE" (242; P/N 24231) N/A
TORQUE REQUIREMENTS
ALL TORQUE VALUES ARE +/- 15%
SIZE
"A"
MOTOR POWER
WIRES TO VFD
(In-lbs / Nm)
"B"
VIBRATION MOUNT
TO BAR BRACKET
(In-lbs / Nm)
VIBRATION
MOUNT
THREAD
SIZE
"C"
VFD NUT TO
VIBRATION MOUNT
(Ft-lbs / Nm)
A5 5 / 0.6
SEE NOTE #7
M6 X 1 4.3 / 5.8
B1 16 / 1.8 M8 X 1.25 11.3 / 15.3
B2 40 / 4.5 M8 X 1.25 11.3 / 15.3
C1 89 / 10 M8 X 1.25 11.3 / 15.3
C2 124 / 14 M8 X 1.25 11.3 / 15.3
TORQUE REQUIREMENTS
ALL TORQUE VALUES ARE +/- 15%
MOTOR
SIZE BOLT SIZE "D" MOTOR BOLT
TO BAR BRACKET
(FT-LBS / NM)*
143-145 5/16 X 18 11.5 / 15.6
182-215 3/8 X 16 20 / 27
254-286 1/2 X 13 49 / 66
324-365 5/8 X 11 98 / 133
404-449 3/4 X 10 173 / 235
1
2
9
3
10 11
"D"
A
DETAIL A
SCALE 1 : 4
"C" "B"
APPLY LOCK TIGHT
BAR SIDE ONLY
6
7
8
4
5
"D"
9
"A"
10 11
1.Items specified on this drawing are specifically for the SKV or SKS product series.
2.Assemble safety strap onto isolation mount stud to produce orientation shown in the assembly drawing.
3.Apply 'Loctite' to isolation mount stud threads (1 place) on all 4x parts.
4.Assemble threaded stud with 'Loctite' into bar bracket until surfaces are in contact without gaps.
5.Use strap wrench for isolation mounts. Screw mount into bar bracket (#2) until the rubber face is flush against the
bar. Torque the mount 1/4 of a full turn.
6.Support VFD & assemble onto 4 isolation mounts simultaneously, assemble lockwashers & nuts, torque to specifi-
cations "C", remove VFD support.
7.Assemble the motor so the feet are angled between 22.5° to 45° offset from the flanges, as shown below.
8.Assemble the motor so the VFD and motor conduit box are hanging over the outlet volute.
9.* = all "D" bolt connections are SAE J429 grade #2 steel - nickel plated.

Taco® SKV
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© 2017 Taco, Inc.
7.3 VFD Mounting to Wall
7.3.1 Lifting
• Check the weight of the unit to determine a safe lift-
ing method.
• Ensure that the lifting device is suitable for the task.
• If necessary, plan for a hoist, crane, or forklift with the
appropriate rating to move the unit.
• For lifting, use hoist rings on the unit, when provided.
7.3.2 Mounting
• Mount the unit vertically.
• The frequency converter allows side by side installa-
tion.
• Ensure that the strength of the mounting location will
support the unit weight.
• Mount the unit to a solid flat surface or to the optional
back plate to provide cooling airflow (see Figure 7-2
and Figure 7-3).
• Improper mounting can result in overheating and
reduced performance.
• Use the slotted mounting holes on the unit for wall
mounting, when provided.
Figure 7-2: Proper Mounting with Back Plate
Item A is a back plate properly installed for required air-
flow to cool the unit.
Figure 7-3: Proper Mounting with Railings
NOTE: Back plate is required when mounted
on railings.
7.3.3 Tightening Torques
See “17.2 Connection Tightening Torques” on page 77
for proper tightening specifications.
7.4 Pump Piping – Detailed
In order to achieve the full added value of the Vertical In-
Line pump design, it is important that you ensure the
pump is affixed to the system piping by the pump flanges
and the pump and motor assembly is allowed to float
freely with the expansion and contraction of the piping
system. Should any vertical in-line pump use supports to
the structure, it is imperative that no pipe strain is
imposed on the pump flanges. Compliant mounts such
as springs or “waffle”-style isolation pads should be used
under the pipe supports if the pump is not truly pipe
mounted.
Various installation arrangements are detailed in the fig-
ures that follow.
Figure 7-4: Hanger Supported, Pipe Mounted
NOTE: The pump should not be rigidly attached to the base/pad structure unless flexible couplings are used.

Taco® SKV
7302-365, Effective: June 5, 2017
© 2017 Taco, Inc.
Vertical In-Line pumps may be installed directly in the
system piping with no additional support. Pipe hangers
are simply sized for the additional weight of the pumping
unit. Many pumps are installed in this manner and are
mounted at sufficient height to take zero floor space.
(Figure 7-4)
Piping for smaller in-line pumps (typically 15 hp and
below) is hung close to the ceiling in many mechanical
rooms. Larger pumps are often mounted near ground
level for ease of maintenance. Figure 7-5 illustrates such
an arrangement with the piping supported at the ceiling
and the vertical pump installed with a Taco Suction Dif-
fuser (RSP) and Plus Two Multi-Purpose Valve.
Figure 7-5: Pipe Mounted, Supported at Ceiling
Should additional space saving be required, the dis-
charge spool piece and Plus Two Multi-Purpose Valve
may be replaced by a long-radius elbow and the Plus
Two Multi-Purpose Valve field converted to a straight pat-
tern configuration and installed in the vertical discharge
pipe (Figure 7-6).
Figure 7-6: Discharge Elbow for Minimum
Footprint
A similar arrangement to Figure 7-5 with additional floor
mounted pipe-stools isolated from the structure by 'waf-
fle' style isolation pads under the Suction Diffuser (RSP)
and Plus Two Multi-Purpose Valve is illustrated in
(Figure 7-7).
Figure 7-7: With Additional Pipe Supports
Floor mounted saddle supports (Figure 7-8) are typical
for condenser water pumps where cooling tower base is
near mechanical room elevation.
Figure 7-8: Floor Saddle Support
Where required, additional floor support may be used as
shown in Figure 7-9. Install a “waffle” isolation pad under
the pump. NOTE: The pump should not be rigidly
attached to the base/pad structure.
Figure 7-9: Additional Floor Support
Stanchion plates at the pump suction and discharge ports
may be supplied for installation convenience. Isolation

Taco® SKV
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© 2017 Taco, Inc.
pads must be used under the legs and monitored as pipe
hangers are adjusted to ensure the pump flanges are not
supporting the piping. Bolting to the floor or housekeep-
ing pad is not recommended. If the stanchions are bolted
down the bolts must be isolated from the stanchion or
inertia base and flexible pipe connectors used (Figure 7-
10).
Figure 7-10: With Stanchion Plates
An installation with stanchion plates for seismically active
regions is illustrated in Figure 7-11. Seismically rated iso-
lation pads or snubbers with bolts isolated from the stan-
chion plates are installed to restrain the pump during a
seismic event. Pipe hangers carry the weight of the
equipment as seismic components are designed only to
restrain the equipment during a seismic event.
Figure 7-11: Installation in Seismically Active
Region
In systems utilizing grooved pipe, flange adapter locking
devices or welded flanges at the pump should be used to
prevent the possibility of pipe mounted pumps rotating in
the piping (Figure 7-12).
Figure 7-12: Mounting in Grooved Pipe Systems
DO NOT support the unit by the motor eye bolts
(Figure 7-13) or by any other part of the motor.
Figure 7-13: Motor Lifting Hook Supported
Connecting the pump to a permanent rigid base
(Figure 7-14) is not recommended unless isolated from
the piping by flexible connectors and the base isolated
from the building structure on an inertia base. (Figure 7-
14 is generally acceptable when using plastic piping.)
Figure 7-14: Mounted on Rigid Base without
Flexible Connectors
NOTE: The pump should not be rigidly attached to the base/pad structure unless flexible couplings are used.

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8 ELECTRICAL CONNECTIONS
8.1 Exploded Views
Figure 8-1: Exploded View A Size
1 LCP 10 Motor output terminals 96 (U), 97 (V), 98 (W)
2 RS-485 serial bus connector (+68, -69) 11 Relay 1 (01, 02, 03)
3 Analog I/O connector 12 Relay 2 (04, 05, 06)
4 LCP input plug 13 Brake (-81, +82) and load sharing (-88, +89) terminals
5 Analog switches (A53), (A54) 14 Line power input terminals 91 (L1), 92 (L2), 93 (L3)
6 Cable strain relief / PE ground 15 USB connector
7 Decoupling plate 16 Serial bus terminal switch
8 Grounding clamp (PE) 17 Digital I/O and 24 V power supply
9 Shielded cable grounding clamp and strain relief 18 Control cable coverplate

Taco® SKV
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Figure 8-2: Exploded View B and C Sizes
8.2 Electrical Installation
This section contains detailed instructions for wiring the adjustable frequency drive. The following tasks are described.
• Wiring the motor to the adjustable frequency drive output terminals
• Wiring the AC line power to the adjustable frequency drive input terminals
• Connecting control and serial communication wiring
• After power has been applied, checking input and motor power; programming control terminals for their intended
functions
1 LCP 11 Relay 2 (04, 05, 06)
2 Cover 12 Lifting ring
3 RS-485 serial bus connector 13 Mounting slot
4 Digital I/O and 24 V power supply 14 Grounding clamp (PE)
5 Analog I/O connector 15 Cable strain relief / PE ground
6 Cable strain relief / PE ground 16 Brake terminal (-81, +82)
7 USB connector 17 Load sharing terminal (DC bus) (-88, +89)
8 Serial bus terminal switch 18 Motor output terminals 96 (U), 97 (V), 98 (W)
9 Analog switches (A53), (A54) 19 Line power input terminals 91 (L1), 92 (L2), 93 (L3)
10 Relay 1 (01, 02, 03)

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Figure 8-3 shows a basic electrical connection.
Figure 8-3: Basic Wiring Schematic Drawing
DANGER: EQUIPMENT HAZARD! Rotating shafts and electrical equipment can be hazardous. All electri-
cal work must conform to national and local electrical codes. It is strongly recommended that installation,
start-up, and maintenance be performed only by trained and qualified personnel. Failure to follow these
guidelines could result in death or serious injury.
CAUTION: WIRING ISOLATION! Run input power, motor wiring and control wiring in three separate
metallic conduits or use separated shielded cable for high frequency noise isolation. Failure to isolate
power, motor and control wiring could result in less than optimum adjustable frequency drive and associ-
ated equipment performance.

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For your safety, comply with the following require-
ments:
• Electronic controls equipment is connected to haz-
ardous AC line voltage. Extreme care should be
taken to protect against electrical hazards when
applying power to the unit.
• Run motor cables from multiple adjustable frequency
drives separately. Induced voltage from output motor
cables run together can charge equipment capacitors
even with the equipment turned off and locked out.
8.2.1 Overload and Equipment Protection
• An electronically activated function within the adjust-
able frequency drive provides overload protection for
the motor. The overload calculates the level of
increase to activate timing for the trip (controller out-
put stop) function. The higher the current draw, the
quicker the trip response. The overload provides
Class 20 motor protection. See “14 Warnings and
Alarms” on page 61 for details on the trip function.
• Because the motor wiring carries high frequency cur-
rent, it is important that wiring for line power, motor
power, and control is run separately. Use metallic
conduit or separated shielded wire. Failure to isolate
power, motor, and control wiring could result in less
than optimum equipment performance. See Figure 8-
4.
Figure 8-4: Proper Electrical Installation Using
Flexible Conduit
All adjustable frequency drives must be provided with
short-circuit and overcurrent protection. Input fusing is
required to provide this protection, see Figure 9.2.3. If not
factory supplied, fuses must be provided by the installer
as part of installation.
Figure 8-5: Adjustable Frequency Drive Fuses
Wire Type and Ratings
• All wiring must comply with local and national regula-
tions regarding cross-section and ambient tempera-
ture requirements.
• Danfoss recommends that all power connections be
made with a minimum 167°F [75 °C] rated copper
wire.
8.3 Grounding Requirements
DANGER: GROUNDING HAZARD! For
operator safety, it is important to ground
adjustable frequency drive properly in accor-
dance with national and local electrical
codes as well as instructions contained
within these instructions. Ground currents
are higher than 3.5 mA. Failure to ground the
adjustable frequency drive properly could
result in death or serious injury.
NOTE: It is the responsibility of the user or certified elec-
trical installer to ensure correct grounding of the equip-
ment in accordance with national and local electrical
codes and standards.
• Follow all local and national electrical codes to
ground electrical equipment properly.
• Proper protective grounding for equipment with
ground currents higher than 3.5 mA must be estab-
lished, see Leakage Current (>3.5 mA).
• A dedicated ground wire is required for input power,
motor power and control wiring.

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• Use the clamps provided with on the equipment for
proper ground connections.
• Do not ground one adjustable frequency drive to
another in a “daisy chain” fashion.
• Keep the ground wire connections as short as possi-
ble.
• Use of high-strand wire to reduce electrical noise is
recommended.
• Follow the motor manufacturer wiring requirements.
8.3.1 Leakage Current (>3.5 mA)
Follow national and local codes regarding protective
grounding of equipment with a leakage current > 3.5 mA.
Adjustable frequency drive technology implies high fre-
quency switching at high power. This will generate a leak-
age current in the ground connection. A fault current in
the adjustable frequency drive at the output power termi-
nals might contain a DC component which can charge
the filter capacitors and cause a transient ground
current. The ground leakage current depends on
various system con"gurations including RFI filtering,
shielded motor cables, and adjustable frequency drive
power.
EN/IEC61800-5-1 (Power Drive System Product Stan-
dard)
requires special care if the leakage current exceeds
3.5mA.
Grounding must be reinforced in one of the following
ways:
• Ground wire of at least 0.0155 in2 [10mm2]
• Two separate ground wires both complying with the
dimensioning rules
See EN/IEC61800-5-1 and EN50178 for further informa-
tion.
8.3.2 Using RCDs
Where residual current devices (RCDs), also known as
ground leakage circuit breakers (ELCBs), are used, com-
ply with the following:
• Use RCDs of type B only which are capable of
detecting AC and DC currents
• Use RCDs with an inrush delay to prevent faults due
to transient ground currents
• Dimension RCDs according to the system configura-
tion and environmental considerations
8.3.3 Grounding Using Shielded Cable
Grounding clamps are provided for motor wiring (see
Figure 8-6).
Figure 8-6: Grounding with Shielded Cable
8.3.4 Grounding Using Conduit
DANGER: GROUNDING HAZARD! Do not
use conduit connected to the adjustable fre-
quency drive as a replacement for proper
grounding. Ground currents are higher than
3.5 mA. Improper grounding can result in
personal injury or electrical shorts.
Dedicated grounding clamps are provided (See Figure 8-
7).
Figure 8-7: Grounding with Conduit
1.Use a wire stripper to remove the insulation for
proper grounding.
2.Secure the grounding clamp to the stripped portion
of the wire with the screws provided.
3.Secure the grounding wire to the grounding clamp
provided.

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8.3.5 Motor Connection
DANGER: INDUCED VOLTAGE! Run out-
put motor cables from multiple adjustable
frequency drives separately. Induced voltage
from output motor cables run together can
charge equipment capacitors even with the
equipment turned off and locked out. Failure
to run output motor cables separately could
result in death or serious injury.
• For maximum wire sizes, see “17.1 Power-depen-
dent Specifications” on page 75.
• Comply with local and national electrical codes for
cable sizes.
• Motor wiring knockouts or access panels are pro-
vided at the base of IP21 and higher (NEMA1/12)
units
• Do not install power factor correction capacitors
between the adjustable frequency drive and the
motor
• Do not wire a starting or pole-changing device
between the adjustable frequency drive and the
motor.
• Connect the 3-phase motor wiring to terminals 96
(U), 97 (V), and 98 (W).
• Ground the cable in accordance with grounding
instructions provided.
• Follow the motor manufacturer wiring requirements
The three following figures represent line power input,
motor, and grounding for basic adjustable frequency
drives. Actual configurations vary with unit types and
optional equipment.
Figure 8-8: Motor, Line Power and Ground Wiring
for A-Frame Sizes
Figure 8-9: Motor, Line Power and Ground Wiring
for B-Frame Sizes and Above Using Shielded
Cable
Figure 8-10: Motor, Line Power and Ground
Wiring B-Frame Sizes and Above Using
Shielded Cable or Conduit
8.3.6 AC Line Power Connection
Size wiring based upon the input current of the adjustable
frequency drive.
• Comply with local and national electrical codes for
cable sizes.
• Connect 3-phase AC input power wiring to terminals
L1, L2, and L3 (see Figure 8-11).

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• Depending on the configuration of the equipment,
input power will be connected to the line power input
terminals or the input disconnect.
Figure 8-11: Connecting to AC Line Power
• Ground the cable in accordance with grounding
instructions provided in “8.3 Grounding Require-
ments” on page 12.
• All adjustable frequency drives may be used with an
isolated input source as well as with ground refer-
ence power lines. When supplied from an isolated
line power source (IT line power or floating delta) or
TT/TN-S line power with a grounded leg (grounded
delta), set 14-50 RFI 1 to OFF. When off, the internal
RFI filter capacitors between the chassis and the
intermediate circuit are isolated to avoid damage to
the intermediate circuit and to reduce ground capac-
ity currents in accordance with IEC 61800-3.
8.3.7 Control Wiring
Isolate control wiring from high power components in the
adjustable frequency drive.
If the adjustable frequency drive is connected to a therm-
istor, for PELV isolation, optional thermistor control wiring
must be reinforced/ double insulated. A 24 VDC supply
voltage is recommended.
Access
Remove access coverplate with a screwdriver. See “Fig-
ure 8-12: Control Wiring Access for A2, A3, B3, B4, C3
and C4 Enclosures” on page 15.
Or remove front cover by loosening attaching screws.
See “Figure 8-13: Control Wiring Access for A4, A5, B1,
B2, C1 and C2 Enclosures” on page 15.
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Figure 8-12: Control Wiring Access for A2, A3,
B3, B4, C3 and C4 Enclosures
Figure 8-13: Control Wiring Access for A4, A5,
B1, B2, C1 and C2 Enclosures
Please see the table below before tightening the covers.
Table 1: Tightening Torques for Covers (Nm)
Frame IP20 IP21 IP55 IP66
A4/A5 - - 2 2
B1 - * 2.2 2.2
B2 - * 2.2 2.2
C1 - * 2.2 2.2
C2 - * 2.2 2.2
* No screws to tighten
- Does not exist

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Control Terminal Types
Figure 8-14 shows the removable adjustable frequency
drive connectors.
Figure 8-14: Control Terminal Locations
• Connector 1 provides four programmable digital
inputs terminals, two additional digital terminals pro-
grammable as either input or output, a 24V DC termi-
nal supply voltage, and a common for optional
customer supplied 24V DC voltage.
• Connector 2 terminals (+)68 and (-)69 are for an RS-
485 serial communications connection.
• Connector 3 provides two analog inputs, one analog
output, 10V DC supply voltage, and commons for the
inputs and output.
• Connector 4 is a USB port available for use with the
MCT-10 Set-up Software.
• Also provided are two Form C relay outputs that are
in various locations depending upon the adjustable
frequency drive configuration and size.
Wiring to Control Terminals
Control terminal connectors can be unplugged from the
adjustable frequency drive for ease of installation, as
shown in Figure 8-15.
Figure 8-15: Unplugging Control Terminals
1.Open the contact by inserting a small screwdriver
into the slot above or below the contact, as shown
in Figure 8-16.
2.Insert the bared control wire into the contact.
3.Remove the screwdriver to fasten the control wire
into the contact.
4.Ensure the contact is firmly established and not
loose. Loose control wiring can be the source of
equipment faults or less than optimal operation.
Figure 8-16: Connecting Control Wiring
Using Shielded Control Cables
Correct Shielding
The preferred method in most cases is to secure control
and serial communication cables with shielding clamps
provided at both ends to ensure best possible high fre-
quency cable contact.

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50/60 Hz ground loops
With very long control cables, ground loops may occur.
To eliminate ground loops, connect one end of the shield-
toground with a 100 nF capacitor (keeping leads short).
Avoid EMC noise on serial communication
To eliminate low-frequency noise between adjustable fre-
quency drives, connect one end of the shield to terminal
61. This terminal is connected to ground via an internal
RC link. Use twisted-pair cables to reduce interference
between conductors.
Control Terminal Functions
Adjustable frequency drive functions are commanded by
receiving control input signals.
• Each terminal must be programmed for the function it
will be supporting in the parameters associated with
that terminal.
• It is important to confirm that the control terminal is
programmed for the correct function. See “9 User
Interface” on page 28for details on accessing param-
eters..
• The default terminal programming is intended to initi-
ate adjustable frequency drive functioning in a typical
operational mode.
Jumper Terminals 12 and 27
A jumper wire may be required between terminal 12 (or
13) and terminal 27 for the adjustable frequency drive to
operate when using factory default programming values.
• Digital input terminal 27 is designed to receive an
24VDC external interlock command. In many appli-
cations, the user wires an external interlock device to
terminal 27.
• When no interlock device is used, wire a jumper
between control terminal 12 (recommended) or 13 to
terminal 27. This provides an internal 24 V signal on
terminal 27.
• No signal present prevents the unit from operating.
• When the status line at the bottom of the LCP reads
“AUTO REMOTE COASTING” or “Alarm 60 External
Interlock” is displayed, this indicates that the unit is
ready to operate but is missing an input signal on ter-
minal 27.
• When factory installed optional equipment is wired to
terminal 27, do not remove that wiring.
Terminal 53 and 54 Switches
• Analog input terminals 53 and 54 can select either
voltage (0 to 10V) or current (0/4–20mA) input sig-
nals
• Remove power to the adjustable frequency drive
before changing switch positions.
• Set switches A53 and A54 to select the signal type. U
selects voltage, I selects current.
• The switches are accessible when the LCP has been
removed (see Figure 8-17). Note that some option
cards available for the unit may cover these switches
and must be removed to change switch settings.
Always remove power to the unit before removing
option cards.
• Terminal 53 default is for a speed reference signal in
open-loop set in 16-61 Terminal 53 Switch Setting
• Terminal 54 default is for a feedback signal in closed-
loop set in 16-63 Terminal 54 Switch Setting
Figure 8-17: Location of Terminals 53 and 54
Switches

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8.4 Typical Terminal Wiring Configurations
The unit connection blocks are shown in “Figure 8-14: Control Terminal Locations” on page 16.
Table 2: Control Terminal Information
Terminal
number Parameter Default setting Description
Relay Outputs 01, 02, 03 5-40 Relay 1 [160] No Alarm Form C Relay Output. Used for AC or DC voltages and either
resistive or inductive loads. see the following section on relay
wiring for contact current and voltage ratings.
04, 05, 06 5-40 Relay 2 [5] Running
Connector 1 12, 13 - +24 V DC 24 V DC supply voltage. Maximum output current is 200 mA
total for all 24 V loads. Intended for digital inputs, external
transducers.
18 5-10 [8] Start Start/Stop digital input signal for the drive. Connect input to 24
V to start. Open the input to stop the drive.
19 5-11 [0] No Operation Digital input (not used)
27 5-12 [0] No Operation Digital input (not used)
29 5-13 [0] No Operation Digital input (not used)
32 5-14 [0] No Operation Digital input (not used)
33 5-15 [0] No Operation Digital input (not used)
20 - Common Common for digital inputs and reference for 24 V supply
Connector 2 61 - Shield Connection Integrated RC filter for cable shield. ONLY for connecting the
shield when experiencing EMC problems.
68 8-3 + RS485 Interface (+)
69 8-3 - RS485 Interface (-)
Connector 3 39 - AO Common Common for analog output
42 6-50 4-20mA Motor
Freq
Analog output. Default setting is 4-20mA signal (500 ohms
maximum) based on motor speed.
50 - +10 V DC 10 V DC analog supply voltage. 15mA max.
53 6-1 [0] No Operation Analog input 53.
54 6-2 [0] No Operation Analog input 54.
55 - AI Common Common for analog input.

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Figure 8-18: Control Terminal Connectors 1-4 and Relay Output Locations
Drive 1 Relay. Relay
1 is on the right in
this view.
Relay 2.

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8.4.1 Factory default set-up
This configuration makes use of the controller factory default settings for input/output. The factory default settings are
configured for Set-up 1, SelfSensing system curve control without an external transducer. No parameters need to be
changed to use this configuration. Set-up 3, SelfSensing constant flow control, uses the same default settings.
Set-ups can be changed by modifying the parameter 0-10 Active Set-up.
NOTE: The factory default settings require a start signal wired to DI18 (see below).
69
-
39
COM
42
AOUT
50
+10V
53
A IN
55
COM
54
A IN
12
+24V
13
+24V
18
D IN
19
D IN
27
D IN
29
D IN
32
D IN
33
D IN
20
COM
68
+
61
SHLD
Comm Port I/O Analog I/O Digital
Starting/Stopping
Controller
[5-10]
[8] Start*
Start: Closed
* factory default