Fairway Farms Swim Club

Pool Main Pump Motor: Difference between revisions

Page Discussion

Pool Main Pump Motor (view source)

Revision as of 11:34, 20 March 2022

2,698 bytes added ,  4 years ago
→‎VFD Unit
VisualWikitext
 
(42 intermediate revisions by the same user not shown)
Line 9: Line 9:
=== Starting and Stopping ===
=== Starting and Stopping ===


This is performed via the motor starter. Further details on hold, pending replacement with a VFD.
Prior to the spring of 2022, this was performed via pushbuttons on the motor starter.
 
Further details will be posted once the VFD is brought up.


=== Flow Adjustment ===
=== Flow Adjustment ===


The pump flow is adjusted via the butterfly valve on the output side of the pump.  The flow rate must be periodically adjusted via this valve as debris in the strainer basket and sand filters provides additional resistance.
Prior to the spring of 2022, pump flow was manually adjusted via the butterfly valve on the output side of the pump.  


In the future, a VFD may be used to reduce the motor speed, eliminating the need for manual adjustment via a valve.
Flow adjustment will be automatic with the VFD (details to follow).


== Maintenance ==
== Maintenance ==
Line 24: Line 26:


== Wiring and Fuse Protection ==
== Wiring and Fuse Protection ==
The motor is supplied 3-phase "high-leg delta" 240 VAC.  This is an asymmetrical supply (relative to earth ground); see measurements in the [[#Appendix|appendix]].  There are two disconnects: one in the basement of the clubhouse (fused at 100 A) and one in the pump house (fused at 60 A).  See the [[Electrical System]] diagram for details.


The existing motor is fed by 3 x TBD (#10 AWG GND).  Fused with 3 x FRN-R-60 (60 A) fuses.
The existing motor is fed by 3 x TBD (#10 AWG GND).  Fused with 3 x FRN-R-60 (60 A) fuses.


== Variable Frequency Drive ==
== Thermal Monitoring ==


<b>IMPORTANT:</b> At this time, this section is for investigation purposes only.  It has not been determined when/if a VFD will be implemented.
At this time, no thermal monitoring is performed on the motor.  It does not appear the motor has any embedded temperature sensors.  The possibility of adding thermocouples is being investigated.


=== Justification ===
== Variable Frequency Drive ==


As of Fall 2021, the pump is controlled by a Square D 8536 latching motor starter (relay).  The pump is manually operated via start and stop pushbuttons.  The flow rate is adjusted via the butterfly valve on the output side of the pump.
=== Background ===


Removal of the motor starter and replacement with a VFD has been proposed.  This system would be implemented prior to the 2022 swim season.
Prior to the spring of 2022, the main pump motor was controlled by a Square D 8536 latching motor starter (relay).  Start and stop operations were manually performed by pushbuttons.  Adjustment of the flow rate was only possible by positioning the butterfly valve on the output side of the pump.


Benefits to changing to the VFD include:
Benefits to changing to the VFD include:


* Motor speed can be automatically adjusted (via the [[Pool Systems Automation|automation system]]) to compensate for changes in flow rate due to the state of the strainer basket and sand filters.  A constant and flow rate can be assured until the strainer basket or filters become too clogged.  The automation system is NOT required to operate the drive.  In the event that the automation system is not operational (or remote VFD control is disabled), the VFD can be operated with start and stop pushbuttons in a manner very similar to that of the motor starter.
* The main pump motor speed can be automatically adjusted (via the [[Pool Systems Automation|automation system]]) to compensate for changes in flow rate due to the state of the strainer basket and [[Pool Filter Tanks|sand filters]].  A constant flow rate can be assured until the strainer basket or filters become too clogged.  The automation system is NOT required to operate the drive.  In the event that the automation system is not operational (or remote VFD control is disabled), the VFD can be operated with start and stop pushbuttons in a manner very similar to that of the motor starter.
* No need for the operator (managers or B&G personnel) to regularly adjust the flow rate due to changing conditions.  An improper flow rate:
* No need for the operator (the pool manager or B&G personnel) to regularly adjust the flow rate due to changing conditions.  An improper flow rate:
** Violates best practices and/or health department requirements if too low (minimum number of complete water turn-over cycles per 24 hour period).
** Violates best practices and/or health department requirements if it is too low (there is a required minimum number of complete water turn-over cycles per 24 hour period).
** Causes channeling in the sand filters due if too high.  This can lead to incomplete filtration (cloudy water) and requires opening and manually stirring tank sand to resolve.
** Causes channeling in the sand filters due if it is too high.  This can lead to incomplete filtration (cloudy water) and requires opening and manually stirring tank sand to resolve.
* Utility incentives will pay for a significant portion of the material cost.  As of 2022, DTE will reimburse up to $900 for a 15 HP VFD.
* Utility incentives will pay for a significant portion of the material cost.  At the time of the project, DTE reimbursed up to $900 for a 15 HP VFD.
* Enhanced safety with the addition of two emergency stop buttons, including one at the gallery level (near the pump).
* Enhanced safety with the addition of two emergency stop buttons, including one at the gallery level (near the pump).
* Reduced stress on the mechanical system during startup as the motor speed can be ramped up rather than instant-on.  This prevents "hammering" that can occur from an abrupt start.
* Reduced stress on the mechanical system during startup as the motor speed can be ramped up rather than instant-on.  This prevents "hammering" that can occur from an abrupt start.
* Improved fault detection.  The drive can detect shorts, over-current events, low voltage, phase loss, etc.  The existing configuration relies solely upon fuses, which may not offer the same level of protection.
* Improved fault detection.  The drive can detect shorts, over-current events, low voltage, phase loss, etc.  The existing configuration relies solely upon fuses, which may not offer the same level of protection.
* Improved [https://www.enelx.com/n-a/en/stories/3-reasons-pay-attention-poor-power-factor power factor].  An improved power factor reduces losses in the cabling between the distribution panel in the clubhouse basement and the pump house.


There are some downsides, too:
There are some downsides, too:


* Material cost (see the [[#Bill of Materials|bill of materials]]).
* The material cost (see the [[#Bill of Materials|bill of materials]]).  This is managed by creative purchasing - utilizing refurbished and surplus materials where possible.
* Added complexity.
* Some added complexity.
* Added failure points - including the addition of sensitive electronics in a harsh environment.
* Added failure points - including the addition of sensitive electronics in a harsh environment (corrosive vapors and dust).


An improvement in energy efficiency may be possible.  However, it is not confirmed.  Restricting the output flow on a centrifugal pump reduces the amount of work (pushing a lower volume weight of water).  Data in the appendix below confirms this to a point.
An improvement in energy efficiency may be possible.  However, it is not confirmed.  Restricting the output flow on a centrifugal pump reduces the amount of work (pushing a lower volume weight of water).  Data in the appendix below confirms this to a point.
=== Requirements ===
* Must withstand an ambient operating range in the 40 &deg;C to 50 &deg;C (122 &deg;F) range.  For the GS23-2015 at 75% load, 50 &deg;C, no de-rating is necessary up to a 4 kHz carrier frequency (SVPWM mode).
* Must be compatible with 240 VAC high-leg delta.
* A two-channel safety relay will be used.


=== Theory of Operation ===
=== Theory of Operation ===


The sections below are theoretical at this point, describing possible operation for the VFD controls.
NOTE: The sections that follow are still under development.


==== Reset ====
==== Reset ====
Line 98: Line 97:
=== VFD Unit ===
=== VFD Unit ===


Cost is a major driver in the VFD selection process.  As noted, up to $900 will be reimbursed by DTE.  Longevity is an issue, too, as failure becomes a MAJOR issue for pool operation.
This section has been updated to alter its context from research to implementation.  A majority of the data for "other" VFD units has been removed.


The consensus amongst "experts" (i.e. individuals with opinions in forums) is that:
Yaskawa GA50U2042ABA:


* ABB or Allen Bradley drives are top-of-the-line, but come at a cost.  ABB drives are very easy to program (but expensive!).
* The 2042 model sized for "normal duty" (ND) 15 HP which is appropriate for variable torque (VT) applications (i.e. centrifugal pumps).
* Automation Direct drives are inexpensive - but support is lacking.  Later generation drives (such as the GS23, made by Delta) seem to receive positive feedback. Earlier generations (GS1, GS2) are to be avoided. Much of the negative feedback seems to be 10+ years old.
* Internal PCBs are conformally coated (IEC 60721-3-3, Class 3C2 for chemical gasses).  <b>This is a huge plus!</b>
* Delta is usually regarded as "decent".
* Rated for -10 &deg;C to +50 &deg;C (122 &deg;F).
* Teco may be a step up from Automation Direct and Delta?
* 42 A current rating.  Exceeds the FLA of the motor (37 A) with a 14% margin.
* Vacon is well-regarded.
* No built-in DC link reactor (can be added externally between terminals +1 and +2).
* Yaskawa is recommended both in online forums, and by engineers at a local industrial controls firm.
* No built-in EMC filter (desirable for non-symmetric 3-phase supply).
* Frame 5 is 10.24" H x 5.51" W x 5.51" D
* Required vertical-installation clearance is 3.94" top/bottom, 1.18" sides.
* 391 W total loss @ 2 kHz, 42 A output.


For now, the Automation Direct GS23-2015 is the front-runner, but it may be replaced by a Yaskawa drive (TBD).
{| class="wikitable"
!colspan="2"|Drive Catalog Code
!Description
!Comment
|-
!Product Series
|GA50
|
|
|-
!Region Code
|U
|Americas
|
|-
!Input Power Supply Voltage
|2
|Three-Phase AC 200 V Class
|
|-
!Rated Output Current
|42
|42 A
|
|-
!EMC Noise Filter
|A
|No Internal EMC Filter
|
|-
!Enclosure Protection Design
|B
|IP20/UL Open Type
|
|-
!Environmental Specification
|A
|Standard
|
|}


==== Configuration ====
==== Prior Considerations ====


This section is very preliminary - more details to follow.
VFDs from various manufacturers were considered during the evaluation process. In particular, the following other drives were evaluated:


* Use Variable Torque (VT) mode for pump control (power is proportional to the cube of the speed).
* ABB ACS310-03U-50A8-2+J400
* Automation Direct GS23-2015
* Automation Direct GS4-2015


==== Alternatives Evaluated ====
=== Line Reactor ===


<b>ABB ACS310-03U-50A8-2+J400:</b>
<b><i>This section is currently being revised.</i></b>


TBD
A 3% impedance reactor absorbs transients and prevents nuisance tripping of drives in most applications and is typical for the line side.  A 5% impedance reactor can be used if the harmonic content is severe or if IEEE519 recommendations should be met.  The reactor impedance magnitude is said to be equal to the voltage drop.


<b>Automation Direct GS4-2015:</b>
For 37 FLA (motor rating).  Assume the VFD has about 97% efficiency (given loss is 391 W @ 42 A).


* Substantially larger: 12.60" L x 7.48" W x 7.48" D (versus 8.15" L x 4.29" W x 6.06" D for the GS3).
{| class="wikitable"
* Support for 1-phase operation (not needed for this application).
!Manufacturer
* Slightly reduced CT/VT ratings: 47A/49A vs. 49A/51A for the GS23.
!Part Number
* Slightly worse low temperature rating: -10 &deg;C vs. -20 &deg;C for the GS23 (not an issue).
!Dimensions
* No FOC or torque control mode?
!Rated<br>Voltage
* No USB port?
!Rated<br>Current
* Slightly more/better analog/digital I/O options vs. the GS23 (not needed for this application).
!Impedance
* Might not be compatible with permanent magnet AC motors?
!Estimated<br>Cost
 
!Comment(s)
<b>Yaskawa GA50U2042ABA:</b>
|-
 
|Automation Direct
* Priced at $1,004.76 (Galco).
|LR-2015
* Sized for "normal duty" (ND) which is appropriate for variable torque (VT) applications (i.e. centrifugal pumps).
|4.25" H x 7.2" W x 4.75" D
* Conformally coated PCBs (IEC 60721-3-3, Class 3C2 for chemical gasses). <b>This is a huge plus!</b>
|208/240 V
* 42 A current rating.
|46.2 A
* No built-in EMC filter (necessary for non-symmetric supply).
|0.22 mH<br>(rated)
* Frame 5 is 10.24" H x 5.51" W x 5.51" D
|$179
 
|Recommended for the LR-2015.
=== Line Reactor ===
|-
 
|MTE
Automation Direct recommends an LR-2015 (46.2 A, 0.22 mH, 3-phase, 4.25" H x 7.2" W x 4.75" D) for $179 on Automation Direct.
|RL-04501
 
|4.60" H x 8.91" W x 7.13" D
A 3% impedance reactor absorbs transients and prevents nuisance tripping of drives in most applications.  A 3% impedance line reactor is typical for the line side.  A 5% impedance reactor can be used if the harmonic content is severe or if IEEE519 recommendations should be met.  The reactor impedance magnitude is said to be equal to the voltage drop.
|
 
|45 A
Multiple alternatives to the LR-2015 have been evaluated:
|0.300 mH<br>(rated)
|$289.31 (Galco)
|Very large physical dimensions.
|-
|TCI
|KDRD2L
|
|
|40 A
|
|-
|TCI
|KDRULD42L
|
|600 V
|32 A
|0.861 mH<br>(calculated)
|
|3% @ 575/600V
|-
|TCI
|KLR35BTB
|
|480 V
|35 A
|0.315 mH<br>(calculated)
|
|1.5% @ 480V (0.315 mH), 3% @ 240V
|-
|TCI
|KLR45BTB
|
|480 V
|45 A
|0.490 mH<br>(calculated)
|
|3% @ 480V
|-
|TCI
|KDRULD2L
|
|}


* MTE RL-04501 (45 A, 0.300 mH, 3-phase, 4.60" H x 8.91" W x 7.13" D) for $289.31 on Galco or far less on eBay.  This is a very large part.
* MTE RLW-004601 (42 A, 3.68" H x 6.00" W x 5.76" D).  Not readily available.
* MTE RLW-004601 (42 A, 3.68" H x 6.00" W x 5.76" D).  Not readily available.
* TCI KDRD24L (208/240 VAC 48 A 15 HP, 3-phase, 3% - Low Z, 3.82" H x 6.95" W x 5.57" D).  $195.94 on Galco (eBay TBD).
* TCI KDRD24L (208/240 VAC 48 A 15 HP, 3-phase, 3% - Low Z, 3.82" H x 6.95" W x 5.57" D).  $195.94 on Galco (eBay TBD).
* Hammond CRX0046AC (46 A, 0.21 mH, 15 HP, 3-phase, 3%, 5.00" L x 6.13" H x 4.38" D, 40 Watts).  Not readily available on eBay.
* Hammond CRX0046AC (46 A, 0.21 mH, 15 HP, 3-phase, 3%, 5.00" L x 6.13" H x 4.38" D, 40 Watts).  Not readily available on eBay.
To evaluate further:
* Baldor LRAC04501 (45 A, 0.3 mH).
* For the Yaskawa GA50...2042 Normal Duty (ND) 15 HP, an Yaskawa open frame 3% URX000323 (35 A, 0.35 mH) or 5 % URX00324 (35 A, 0.71 mH) reactor is recommended.


=== Drawings ===
=== Drawings ===
Line 160: Line 248:
The <b>Line Reactor Placement Study</b> sheet has been created to help evaluate the physical fit of multiple line reactors.  To keep the cost low, multiple options are being considered.
The <b>Line Reactor Placement Study</b> sheet has been created to help evaluate the physical fit of multiple line reactors.  To keep the cost low, multiple options are being considered.


Additionally, concurrent designs for the GS23-2015 and GA50U2042ABA are in development.
[[File:FFSC-005 Pg 5 - VFD Panel Layout (GS23-2015).png|300px]]
[[File:FFSC-005 Pg 7 - VFD Panel Reactor Placement Study.png|300px]]
[[File:FFSC-005 Pg 7 - VFD Panel Reactor Placement Study.png|300px]]
[[File:FFSC-005 Pg 10 - Main Pump Motor VFD.png|300px]]
[[File:FFSC-005 Pg 10 - Main Pump Motor VFD (GS23-2015).png|300px]]
[[File:FFSC-005 Pg 11 - Main Pump Motor VFD (GA50U2042ABA).png|300px]]


=== Bill of Materials ===
=== Bill of Materials ===
Line 192: Line 284:
|$150
|$150
|$300
|$300
|Based on $206.25/ea @ Zoro w/ 20% discount.
|Based on $206.25/ea @ Zoro w/ 20% discount.<br>Alternate: Q403018PCI (listed at $80 on eBay, 7-Feb-2022).
|-
|-
|2
|2
Line 210: Line 302:
|$28
|$28
|$83
|$83
|110 A for the GS-2015; 150 A for the GA50U2042ABA.
|-
|-
|1
|1
Line 225: Line 318:
|1
|1
|Marathon 1423570 Power Dist Block
|Marathon 1423570 Power Dist Block
|$25
|$23
|$25
|$23
|Estimated eBay cost.
|Purchased on eBay 12-Jan-2022.
|-
|-
|1
|1
Line 257: Line 350:
=== Motor Cable ===
=== Motor Cable ===


Shielded VFD cabling may be required to contain high-frequency emissions.  Automation Direct has #8 AWG 4-conductor XLPE insulated shielded cable, rated for 50 A at 75 &deg;C (NEC 310.15 (B), assumes 30 &deg;C ambient) for $8.08/ft (August 2021 pricing).  The cable is made in USA by Southwire.  This cable has an OD of 0.87 inches and minimum bend radius of 10 inches.  Calculations suggest a 1-1/4" conduit may be necessary to pull a cable of this diameter with adequate fill margin.  The existing PVC conduit appears to be about 3/4" (to confirm), which would need to be replaced.
Distance from the presumed origin to the motor terminals is estimated at 28 ft (55" mid motor starter to floor, 102" to north wall, 74" to motor horizontal, 92" pit ceiling to floor, 16" wall to motor junction box).
 
Shielded VFD cabling may be required to contain high-frequency emissions.   
 
Assume use of non-metallic conduit (ENT); Table 1, Chapter 9 applies.  Cross-sectional fill of 53% is permitted.  So, for a 1-1/4" ID conduit, cable may have up to a 0.66" diameter.  For a 1-1/2" ID conduit, cable may have up to a 0.80" diameter. VFD cable counts as a single conductor for conduit fill. 
 
* The Yaskawa GA50U2042ABA accepts up to (and recommends) #6 AWG on U/T1, V/T2 and W/T3 terminals.
 
Options under investigation:
 
* Automation Direct has #8 AWG 4-conductor XLPE insulated shielded cable, rated for 50 A at 75 &deg;C (NEC 310.15 (B), assumes 30 &deg;C ambient) for $8.08/ft (August 2021 pricing).  The cable is made in USA by Southwire.  This cable has an OD of 0.87 inches and minimum bend radius of 10 inches.  Calculations suggest a 1-1/4" conduit may be necessary to pull a cable of this diameter with adequate fill margin.  The existing PVC conduit appears to be about 3/4" (to confirm), which would need to be replaced.
 
* In January 2022, there appears to be a low-cost option (on eBay, Michigan-based seller) to purchase Lapp Kabel #760604 (4 x #6 AWG) VFD cable for less than $6/ft.  This cable has an OD of 25.5 mm (1.00 inches).
 
* SAB Cable 08610804 8/4 THHN VFD Cable (eBay option).
 
=== Thermal Considerations ===
 
According to the datasheet, the Yaskawa GA50U2042ABA dissipates 391 W @ 42 A.  Assuming operation at 37 A, and an approximately linear decrease is power dissipation, up to 344 W of power dissipation is expected.  The drive is specified to operate (without de-rating) at up to 50 &deg;C (122 &deg;F).  Assuming that the pump house may reach temperatures exceeding 90 &deg;F, thermal rise must be kept to a minimum.  Assume that no more than 10 &deg;F of temperature rise is allowed (112 &deg;F ambient).
 
Using the formula: CFM = (3.17 * P) / dT (where dT is in &deg;F), CFM = 3.17 * 344 W / 10 &deg;F; 109 CFM.
 
The line reactor dissipates considerably less.  Exact dissipation is TBD; conservatively assume 67 W (KDRD24L value @ 48 A = 85 W; 85 W * 38 A / 48 A = 67 W).  CFM = 3.17 * 67 W / 10 &deg;F; 21 CFM.
 
=== Bypass ===
 
A bypass mechanism can be used to operate a motor in the event of VFD failure.  No wired bypass will be implemented due to cost/space.  However, the component/wire layout will be such that bypass should be possible with minimal effort.


== Prior Modifications Evaluated ==
== Prior Modifications Evaluated ==
Retrieved from "https://wiki.fairwayfarmsswimclub.com/Special:MobileDiff/1363...1463"