Construction_Specifications_AL-12-143.pdf

CONSTRUCTION SPECIFICATIONS

MESCALERO SUMMIT & FENCE CANYON WATER

PROJECT # AL-12-143

MESCALERO APACHE INDIAN RESERVATION

PREPARED BY

INDIAN HEALTH SERVICE

DSFC/OEH&E/AAO

ALBUQUERQUE DISTRICT

APRIL 2013

INDEX OF TECHNICAL PROVISIONS

SUPPLEMENTAL TECHNICAL PROVISIONS

The Albuquerque Area--Indian Health Service/Office of Environmental Health and Engineering (OEHE)--Sanitation Facilities Construction Technical Provisions, August 2012 edition, are incorporated by reference. The provisions are the same as if fully written herein and shall govern this Project except where revised, updated, or supplemented by the Special Provisions and Supplemental Technical Provisions.

IHS/OEHE TECHNICAL PROVISIONS 2012 EDITION (FURNISHED

SEPARATELY BY IHS)

SECTION 1 TRENCH EXCAVATION & BACKFILL FOR PIPELINES

AND APPURTENANT STRUCTURES

SECTION 2 CONCRETE

SECTION 3 REINFORCING STEEL

SECTION 6 GRAVITY SANITARY SEWERS

SECTION 7 SEWER SERVICE LINE

SECTION 11 ROADWAY & SPECIAL UTILITY CROSSINGS

Supplemental Technical Provisions

STP 1.0 Added Technical Provision – SECTION 29, PRESSURE BOOSTING

SYSTEM

TP-2901 SCOPE: Furnish all labor, materials, equipment, and incidentals as required, and perform all operations in connection with the complete installation of water service lines, in strict accordance with the applicable drawings and these specifications. All permits, permissions, or other authorizations required by the tribal or municipal utility authority for tapping and connection are the responsibility and cost of the Contractor.

TP-2902 PRESSURE SYSTEM: The pressure system shall include the following items.

A. Pressure System Cover (Pumphouse): The Contractor shall furnish and install a prefabricated fiberglass cover, Hubbell Power Systems, Hot-box, 924 Lane Avenue, Jacksonville, FL 32254, 904-786-0204, Model Pump Guard PG10000H or equal, to house the pressure system and appurtenances as shown on the drawings. The enclosure shall have inside dimensions listed on the drawings.

The fiberglass enclosure shall be centered over a reinforced concrete slab, dimensions are listed on the drawings. The enclosure top shall be attached to the slab with stainless steel Hilti anchor bolts or similar concrete anchoring device. The enclosure shall have a heating and ventilation system provided by the manufacturer. All nuts and bolts used in the above construction shall be stainless steel.

C. Pressure System Components:

1. Equipment Mounting: The pump motor control box, circuit breaker panel, and associated electrical components shall be remotely mounted inside the adjacent pumphouse building.

3. Booster Pumphouse and Tank Slab Under Enclosure: The

Contractor shall pour a reinforced concrete slab to support the pressure tank and pressure system appurtenances.

Prior to pouring the base slab, the following shall be installed:

a. A 100mm (4”) schedule 40 PVC or ABS sleeve for the waterline.

b. Two 38mm (1 ½”) approved electrical conduits for the pump wiring and enclosure heating & ventilation system.

c. 8-inch thick compacted ¾” gravel base.

The sleeve for the water line and the electrical conduit shall extend from the surface of the concrete to a point 2 feet beyond the edge of the concrete slab. The Contract shall provide wide sweep 90º bends in both of these lines to facilitate the removal or repair the each line in the future.

Excavation for these components shall be backfilled with sand, which is wetted and tamped prior to pouring the slab.

The slab surface work shall have a burnish-trowel finish and shall be smoothed and sloped toward the drain at 6.4 mm per meter (1/4” per foot).

All concrete work shall be in accordance with Section II of the Technical Provisions.

D. Pressure System - Mechanical Components:

1. Pressure Pump System: The contractor shall furnish and install a fully operational “packaged” pressure boosting system equal to a Grundfos Boosterpaq, MC MPC-E3CRE-7, 3hp, 460V, 2.5-inch diameter piping. See STP 2.0 for full technical provisions.

2. Pressure Gauge: The gauges shall be Ashcroft with a pressure range as listed in the drawings (in psi), 4” diameter face, brass stem with ¼” thread. Gauge shall be installed vertically and displayed so that it can be easily read.

3. Ball Valve: Ball valve shall be bronze, rated at 150 psi.

4. Pressure System Piping: All piping shall be galvanized iron.

Teflon tape or Teflon compound required on all threaded connections. The Contractor shall be responsible for making the physical connection of the pressure tank piping to the existing or proposed home water service line.

5. Pressure Relief Valve: Pressure systems with pumps installed capable of producing more than 80 psi at the pressure tank shall have a pressure relief valve installed near the tank, equal to Goulds AV12-07. The valve shall be set to discharge at 75- 80 psi. Nipple and 90 bend shall be provided to direct the discharge to the floor.

6. Heater: The heater shall be supplied by the fiberglass manufacturer.

TP-2903 ELECTRICAL: The Contractor shall furnish and install all electrical components to the place the pressure system in a fully operational and complete condition. All wiring shall be in accordance with the National Electrical Code and applicable State and local electrical codes. Power will be available at the site. Metal boxes and covers shall be used throughout the pressure system enclosure. All metal boxes of electrical components shall be grounded. All wiring shall be neat and orderly in appearance. Conduit shall be used throughout the pressure system between the disconnect, pressure switch, and control box.

A. Service: The Contractor shall supply and install a properly rated circuit breaker in the existing pumphouse service panel. The Contractor shall then connect electrical service from the main service entrance panel to the pressure system circuit breaker with type UF or USE, three conductors with ground. The grounding conductor shall extend from the main service entrance panel to the pressure system circuit breaker panel, ground fault receptacle, pressure switch, motor panel box, and terminate at the top of the pressure pump. All electrical components shall be installed and mounted as shown in the attached layout and schematic drawings, or as specified by the Owner.

The final configuration of all electrical wiring and location shall be specifically approved by the Owner prior to installation.

C. Conduit: Wiring above ground around the pressure tank shall be enclosed in galvanized EMT or schedule 40 PVC conduit and sealed with approved silicone sealant. In no case shall exposed wires be run from component.

All conduits shall be properly connected using manufacturers' recommendations. Connections of conduit into boxes and into the well shall be made with threaded lock nuts.

TP-2911 MEASUREMENT AND PAYMENT: All measurement and payments will be based on completed and accepted work performed in strict accordance with the drawings and specifications and the respective prices and payments shall constitute full compensation for all work complete, including incidentals. No separate payment will be made for testing, excavation, trenching and backfilling or for other items or work covered under this section of the specifications and all costs pertinent to these items shall be included in the applicable unit prices. THERE

WILL BE NO PAYMENT FOR ANY OF THE ITEMS LISTED BELOW

UNTIL THE NEGATIVE BACTERIOLOGICAL RESULTS, AND WRITTEN

PUMP GUARANTEE FOR THE APPLICABLE SYSTEM ARE FURNISHED

AND ACCEPTED BY THE OWNER.

A. Booster Pump System: The booster pump system will be paid for at the unit price in the bid schedule. This price shall include all labor, equipment, materials, and incidentals required to furnish and install a fully operational booster pump system complete with pump, controller, pressure tank, shut-off valves, unions, copper piping, brass tank cross, hose bib, pressure transducer, ball valve, pressure gauges, pressure relief valve, and all other required components for a fully functioning system.

B. Electrical System: Electrical wiring and Pumpsaver shall be paid for at the unit price in the bid schedule. This price shall include all labor, equipment and materials required for furnishing and installing all electrical wiring, conduit, receptacle, heater, complete equipment mounting board, necessary circuit breakers and panels.

C. Booster Pump Enclosure (pumphouse): Fiberglass enclosure shall be paid at the lump sum price in the bid schedule. This price shall include all labor, equipment, excavation, subgrade preparation, compation and material required for furnishing and installing the concrete pad and fiberglass enclosure.

D. Water System Disinfection: Water system disinfection will be included in the installation of the water service line.

TP-2912 SUBMITTALS

A. Booster Pump B. Underground Wire C. Pressure Tank D. Pressure Switch E. Pressure Gauge F. Check Valve G. Pump Protection Equipment H. Enclosure Heater

PUMP INFORMATION FORM

Reservation: Participant Name:

Contractor:

INDIVIDUAL WATER PRESSURE SYSTEM INSTALLATION:

Site Name:

Type of Pump:

Date of Installation:

Pump Manufacturer:

Model:

Serial No.:

HP: , Dia.: Inches, Volts, Phase, RPM

Amperage: Red: Amp, Black: Amp, Yellow: Amp, Voltage: Red to Black: V, Red to Yellow: V, Yellow to Black:

V, STP 2.0 Added Technical Provision – BoosterpaQ Hydro MPC-E (Panel Mount

VFD)

2.1 WORK INCLUDED

A. Variable Speed Packaged Pumping System

2.2 REFERENCE STANDARDS

The work in this section is subject to the requirements of applicable portions of the following standards:

A. Hydraulic Institute B. ANSI – American National Standards Institute C. ASTM – American Society for Testing and Materials D. IEEE – Institute of Electrical and Electronics Engineers E. NEMA – National Electrical Manufacturers Association F. NEC – National Electrical Code G. ISO – International Standards Organization H. UL – Underwriters Laboratories, Inc.

2.3 VARIABLE SPEED PACKAGED PUMPING SYSTEM

A. Furnish and install a pre-fabricated and tested variable speed packaged pumping system to maintain constant water delivery pressure.

B. The packaged pump system shall be a standard product of a single pump manufacturer. The entire pump system including pumps and pump logic controller, shall be designed and built by the same manufacturer.

C. The complete packaged water booster pump system shall be certified and listed by

UL (Category QCZJ – Packaged Pumping Systems) for conformance to U.S. and Canadian Standards.

2.4 PUMPS

A. All pumps shall be ANSI/NSF 61 approved for drinking water.

B. The pumps shall be of the in-line vertical multi-stage design.

C. The head-capacity curve shall have a steady rise in head from maximum to minimum flow within the preferred operating region. The shut-off head shall be a minimum of 20% higher than the head at the best efficiency point.

D. Small Vertical In-Line Multi-Stage Pumps (Nominal flow from 3 to 125 gallons per minute) shall have the following features:

1. The pump impellers shall be secured directly to the pump shaft by means of a splined shaft arrangement.

2. The suction/discharge base shall have ANSI Class 250 flange or internal pipe thread (NPT) connections as determined by the pump station manufacturer.

3. Pump Construction.

a. Suction/discharge base, pump head, motor stool:

Cast iron (Class 30)

b. Impellers, diffuser chambers, outer sleeve:

304 Stainless Steel

c. Shaft 316 or

431 Stainless Steel

d. Impeller wear rings: 304

Stainless Steel

e. Shaft journals and chamber bearings:

Silicon Carbide

f. O-rings: EPDM

Shaft couplings for motor flange sizes 184TC and smaller shall be made of cast iron or sintered steel. Shaft couplings for motor flange sizes larger than 184TC shall be made of ductile iron

(ASTM 60-40-18).

Optional materials for the suction/discharge base and pump head shall be cast 316 stainless steel (ASTM CF-8M) resulting in all wetted parts of stainless steel.

4. The shaft seal shall be a balanced o-ring cartridge type with the following features:

a. Collar, Drivers, Spring: 316 Stainless Steel

b. Shaft Sleeve, Gland Plate: 316 Stainless Steel

c. Stationary Ring: Silicon Carbide

d. Rotating Ring: Silicon Carbide

e. O-rings: EPDM

The Silicon Carbide shall be imbedded with graphite.

5. Shaft seal replacement shall be possible without removal of any pump components other than the coupling guard, shaft coupling and motor. The entire cartridge shaft seal shall be removable as a one piece component. Pumps with motors equal to or larger than 15 hp (fifteen horsepower) shall have adequate space within the motor stool so that shaft seal replacement is possible without motor removal.

E. Large In-line Vertical Multi-Stage Pumps (Nominal flows from

130 to 500 gallons per minute) shall have the following features:

1. The pump impellers shall be secured directly to the smooth pump shaft by means of a split cone and nut design.

2. The suction/discharge base shall have ANSI Class 125 or

Class 250 flange connections in a slip ring (rotating flange) design as indicated in the drawings or pump schedule.

3. Pump Construction.

a. Suction/discharge base, pump head

Ductile Iron (ASTM 65-45-12)

b. Shaft couplings, flange rings:

Ductile Iron (ASTM 65-45-12)

b. Shaft 431

Stainless Steel

c. Motor Stool Cast Iron

(ASTM Class 30)

d. Impellers, diffuser chambers, outer sleeve:

304 Stainless Steel

e. Impeller wear rings: 304

Stainless Steel

f. Intermediate Bearing Journals: Tungsten

Carbide

g. Intermediate Chamber Bearings: Leadless

Tin Bronze

h. Chamber Bushings: Graphite

Filled PTFE I. O-rings: EPDM

4. The shaft seal shall be a single balanced metal bellows cartridge with the following construction:

a. Bellows: 904L

b. Shaft Sleeve, Gland Plate, Drive Collar: 316

c. Stationary Ring: Carbon

d. Rotating Ring: Tungsten

Carbide

e. O-rings: EPDM

5. Shaft seal replacement shall be possible without removal of any pump components other than the coupling guard, motor couplings, motor and seal cover. The entire cartridge shaft seal shall be removable as a one piece component. Pumps with motors equal to or larger than 15 hp (fifteen horsepower) shall have adequate space within the motor stool so that shaft seal replacement is possible without motor removal.

2.5 VARIABLE FREQUENCY DRIVES (Panel Mount)

A. The VFD shall convert incoming fixed frequency single-phase or three-phase AC power into a variable frequency and voltage for controlling the speed of three-phase AC induction motors. The VFD shall be a six-pulse input design, and the input voltage rectifier shall employ a full wave diode bridge; VFD’s utilizing controlled SCR rectifiers shall not be acceptable. The output waveform shall closely approximate a sine wave. The VFD shall be of a PWM output design utilizing current IGBT inverter technology and voltage vector control of the output PWM waveform.

B. The VFD shall include a full-wave diode bridge rectifier and maintain a displacement power factor of near unity regardless of speed and load.

C. The VFD shall produce an output waveform capable of handling maximum motor cable distances of up to 1,000 ft. (unshielded) without tripping or derating.

D. The VFD shall utilize an output voltage-vector switching algorithm, or equivalent, in both variable and constant torque modes. VFD’s that utilize Sine-Coded PWM or Look-up tables shall not be acceptable.

E. VFD shall automatically boost power factor at lower speeds.

F. The VFD shall be able to provide its full rated output current continuously at 110% of rated current for 60 seconds.

G. An empty pipe fill mode shall be available to fill an empty pipe in a short period of time, and then revert to the PID controller for stable operation.

H. Switching of the input power to the VFD shall be possible without interlocks or damage to the VFD at a minimum interval of 2 minutes.

I. Switching of power on the output side between the VFD and the motor shall be possible with no limitation or damage to the VFD and shall require no additional interlocks.

J. The VFD shall have temperature controlled cooling fans for quiet operation, minimized internal losses, and greatly increased fan life.

K. VFD shall provide full torque to the motor given input voltage fluctuations of up to

+10% to -15% of the rated input voltage.

L. The VFD shall provide internal DC link reactors to minimize power line harmonics and to provide near unity power factor. VFD’s without a DC link reactor shall provide a 5% impedance line side reactor.

M. VFD to be provided with the following protective features:

1. VFD shall have input surge protection utilizing MOV’s, spark gaps, and Zener diodes to withstand surges of 2.3 times line voltage for 1.3 msec.

2. VFD shall include circuitry to detect phase imbalance and phase loss on the input side of the VFD.

3. VFD shall include current sensors on all three-output phases to detect and report phase loss to the motor. The VFD will identify which of the output phases is low or lost.

4. VFD shall auto-derate the output voltage and frequency to the motor in the presence of sustained ambient temperatures higher than the normal operating range, so as not to trip on an inverter temperature fault. The use of this feature shall be user-selectable and a warning will be exported during the event. Function shall reduce switching frequency before reducing motor speed.

5. VFD shall auto-derate the output frequency by limiting the output current before allowing the VFD to trip on overload. Speed can be reduced, but not stopped.

6. The VFD shall have the option of an integral RFI filter. VFD enclosures shall be made of metal to minimize RFI and provide immunity.

N. VFD to be provided with the following interface features:

1. VFD shall provide an alphanumeric backlit display keypad, which may be remotely mounted using standard 9-pin cable. VFD may be operated with keypad disconnected or removed entirely. Keypad may be disconnected during normal operation without the need to stop the motor or disconnect power to the VFD.

2. VFD shall display all faults in plain text; VFD’s, which can display only fault codes, are not acceptable.

3. All VFD’s shall be of the same series, and shall utilize a common control card and LCP (keypad/display unit) throughout the rating range. The control cards and keypads shall be interchangeable through the entire range of drives used on the project.

4. VFD keypad shall be capable of storing drive parameter values in non-volatile RAM uploaded to it from the VFD, and shall be capable of downloading stored values to the VFD to facilitate programming of multiple drives in similar applications, or as a means of backing up the programmed parameters.

5. A red FAULT light, a yellow WARNING light and a green POWER-ON light shall be provided. These indications shall be visible both on the keypad and on the VFD when the keypad is removed.

6. A start guide menu with factory preset typical parameters shall be provided on the VFD to facilitate commissioning.

7. VFD shall provide full galvanic isolation with suitable potential separation from the power sources (control, signal, and power circuitry within the drive) to ensure compliance with PELV requirements and to protect PLC’s and other connected equipment from power surges and spikes.

8. All inputs and outputs shall be optically isolated. Isolation boards between the VFD and external control devices shall not be required.

9. There shall be three programmable digital inputs for interfacing with the systems external control and safety interlock circuitry. An additional digital input is preprogrammed for start/stop.

10. The VFD shall have two analog signal inputs. One dedicated for sensor input and one for external set point input.

11. One programmable analog output shall be provided for indication of a drive status.

12. The VFD shall provide two user programmable relays with selectable functions. Two form ‘C’ 230VAC/2A rated dry contact relay outputs shall be provided.

13. The VFD shall store in memory the last 5 faults with time stamp and recorded data.

14. The VFD shall be equipped with a standard RS-485 serial communications port for communication to the multi-pump controller.

The bus communication protocol for the VFD shall be the same as the controller protocol.

O. VFD service conditions:

1. Ambient temperature operating range, -10 to 45ºC (14 to 113F).

2. 0 to 95% relative humidity, non-condensing.

3. Elevation to 1000 meters (3,300 feet) without derating.

4. VFD’s shall be rated for line voltage of 525 to 690VAC, 380 to 480VAC, or 200 to 240VAC; with +10% to -15% variations. Line frequency variation of ± 2% shall be acceptable.

5. No side clearance shall be required for cooling of the units.

2.6 PUMP SYSTEM CONTROLLER

A. The pump system controller shall be a standard product developed and supported by the pump manufacturer.

B. The controller shall be microprocessor based capable of having software changes and updates via personal computer (notebook).

The controller user interface shall have a VGA display with a minimum screen size of 3-1/2” x 4-5/8” for easy viewing of system status parameters and for field programming. The display shall have a back light with contrast adjustment. Password protection of system settings shall be standard.

C. The controller shall provide internal galvanic isolation to all digital and analog inputs as well as all fieldbus connections.

D. The controller shall display the following as status readings from a single display on the controller (this display shall be the default):

Current value of the control parameter, (typically discharge pressure) Most recent existing alarm (if any) System status with current operating mode Status of each pump with current operating mode and rotational speed as a percentage (%)

E. The controller shall have as a minimum the following hardware inputs and outputs:

Three analog inputs (4-20mA or 0-10VDC) Three digital inputs Two digital outputs Ethernet connection Field Service connection to PC for advanced programming and data logging

F. Pump system programming (field adjustable) shall include as a minimum the following:

Water shortage protection (analog or digital) Transducer Settings (Suction and Discharge Analog supply/range) PI Controller (Proportional gain and Integral time) settings High system pressure indication and shut-down Low system pressure indication and shut-down Low suction pressure/level shutdown (via digital contact) Low suction pressure/level warning (via analog signal) Low suction pressure/level shutdown (via analog signal) Flow meter settings (if used, analog signal)

G. The system controller shall be able to accept up to seven programmable set-points via a digital input, (additional input/output module may be required).

H. The controller shall have advanced water shortage protection. When analog sensors (level or pressure) are used for water shortage protection, there shall be two indication levels. One level is for warning indication only (indication that the water level/pressure is getting lower than expected levels) and the other level is for complete system shut-down (water or level is so low that pump damage can occur). System restart after shut-down shall be manual or automatic (user selectable).

I. The system pressure set-point shall be capable of being automatically adjusted by using an external set-point influence. The set-point influence function enables the user to adjust the control parameter (typically pressure) by measuring an additional parameter. (Example:

Lower the system pressure set-point based on a flow measurement to compensate for lower friction losses at lower flow rates).

J. The controller shall be capable of receiving a remote analog set-point

(4-20mA or 0-10 VDC) as well as a remote system on/off (digital) signal.

K. The pump system controller shall store up to 24 warning and alarms in memory. The time, date and duration of each alarm shall be recorded. A potential-free relay shall be provided for alarm notification to the building management system. The controller shall display the following alarm conditions:

High System Pressure Low system pressure Low suction pressure (warning and/or alarm) Individual pump failure VFD trip/failure Loss of sensor signal (4-20 mA) Loss of remote set-point signal (4-20mA) System power loss

L. The pump system controller shall be mounted in a UL Type 3R rated enclosure. A self-certified NEMA enclosure rating shall not be considered equal. The entire control panel shall be UL 508 listed as an assembly. The control panel shall include a main disconnect, circuit breakers for each pump and the control circuit and control relays for alarm functions.

Control panel options shall include, but not be limited to:

Pump Run Lights Pump Alarm Lights System Fault Light Audible Alarm (80 db[A]) Surge Arrestor Control Panel Internal Illumination Emergency/Normal Operation Switches Service Disconnect Switches

M. The controller shall be capable of receiving a redundant sensor input to function as a backup to the primary sensor (typically discharge pressure).

N. The controller shall have a pump “Test Run” feature such that pumps are switched on during periods of inactivity (system is switched to the “off” position but with electricity supply still connected). The inoperative pumps shall be switched on for a period of two to three (2-

3) seconds every 24 hours, 48 hours or once per week (user selectable).

O. The controller shall be capable of displaying instantaneous power consumption (Watts or kilowatts) and cumulative energy consumption (kilowatt-hours).

P. The actual pump performance curves (5th order polynomial) shall be loaded (software) into the pump system controller.

2.7 SEQUENCE OF OPERATION

A. The system controller shall operate equal capacity variable speed pumps to maintain a constant discharge pressure (system set-point).

The system controller shall receive an analog signal [4-20mA] from the factory installed pressure transducer on the discharge manifold, indicating the actual system pressure. As flow demand increases the pump speed shall be increased to maintain the system set-point pressure. When the operating pump(s) reach 96% of full speed (adjustable), an additional pump will be started and will increase speed until the system set-point is achieved. When the system pressure is equal to the system set-point all pumps in operation shall reach equal operating speeds. As flow demand decreases the pump speed shall be reduced while system set-point pressure is maintained.

When all pumps in operation are running at low speed the system controller shall switch off pumps when fewer pumps are able to maintain system demand.

B. The system controller shall be capable of switching pumps on and off to satisfy system demand without the use of flow switches, motor current monitors or temperature measuring devices.

C. All pumps in the system shall alternate automatically based on demand, time and fault. If flow demand is continuous (no flow shut-down does not occur), the system controller shall have the capability to alternate the pumps every 24 hours, every 48 hours or once per week. The interval and actual time of the pump change-over shall be field adjustable.

2.8 LOW FLOW STOP FUNCTION

The system controller shall be capable of stopping pumps during periods of low-flow or zero-flow without wasting water or adding unwanted heat to the liquid. Temperature based no flow shut-down methods that have the potential to waste water and add unwanted temperature rise to the pumping fluid are not acceptable.

Standard Low Flow Stop and Energy Saving Mode If a low or no flow shut-down is required (periods of low or zero demand) a bladder type diaphragm tank shall be installed with a pre-charge pressure of 70% of system set-point. The tank shall be piped to the discharge manifold or system piping downstream of the pump system. When only one pump is in operation the system controller shall be capable of detecting low flow (less than 10% of pump nominal flow) without the use of additional flow sensing devices. When a low flow is detected, the system controller shall increase pump speed until the discharge pressure reaches the stop pressure (system set-point plus 50% of programmed on/off band). The pump shall remain off until the discharge pressure reaches the start pressure (system set-point minus 50% of programmed on/off band). Upon low flow shut-down a pump shall be restarted in one of the following two ways:

A. Low Flow Restart: If the drop in pressure is slow when the start pressure is reached (indicating the flow is still low), the pump shall start and the speed shall again be increased until the stop pressure is reached and the pump shall again be switched off.

B. Normal Flow Restart: If the drop in pressure is fast (indicating the flow is greater than 10% of pump nominal flow) the pump shall start and the speed shall be increased until the system pressure reaches the system set-point.

[OPTIONAL] Low Flow Stop and Energy Saving Mode

The pump system controller shall be capable receiving a digital signal from a flow switch or an analog signal from a flow meter to indicate a low flow condition. A bladder type diaphragm tank shall be installed with a pre-charge pressure of 70% of system set-point.

The tank shall be piped to the discharge manifold or system piping downstream of the pump system. When low flow is detected (signal from flow switch or meter), the system controller shall increase pump speed until the discharge pressure reaches the stop pressure (system set-point plus 50% of programmed on/off band). The pump shall remain off until the discharge pressure reaches the start pressure (system set-point minus 50% of programmed on/off band). The pump shall remain in the energy saving on/off mode during low flow indication. When low flow is no longer present (low flow indication ceases), the pump(s) shall resume constant pressure operation.

It shall be possible to change from the standard low flow stop to the optional low flow stop (and vice-versa) via the user interface.

2.9 SYSTEM CONSTRUCTION

A. The suction and discharge manifolds shall be constructed of 316 stainless steel. Manifold connection sizes shall be as follows:

3 inch and smaller: Male NPT threaded 4 inch through 8 inch: ANSI Class 150 rotating flanges 10 inch and larger: ANSI Class 150 flanges

B. Pump Isolation valves shall be provided on the suction and discharge of each pump. Isolation valve sizes 2 inch and smaller shall be nickel plated brass full port ball valves. Isolation valve sizes 3 inch and larger shall be a full lug style butterfly valve. The valve disk shall be of stainless steel. The valve seat material shall be EPDM and the body shall be cast iron, coated internally and externally with fusion-bonded epoxy.

B. A spring-loaded non-slam type check valve shall be installed on the discharge of each pump. The valve shall be a wafer style type fitted between two flanges. The head loss through the check valve shall not exceed 5 psi at the pump design capacity. Check valves 1-1/2” and smaller shall have a POM composite body and poppet, a stainless steel spring with EPDM or NBR seats. Check valves 2” and larger shall have a body material of stainless steel or epoxy coated iron (fusion bonded) with an EPDM or NBR resilient seat. Spring material shall be stainless steel. Disk shall be of stainless steel or leadless bronze.

C. For systems that require a diaphragm tank, a connection of no smaller than ¾” shall be provided on the discharge manifold.

D. A pressure transducer shall be factory installed on the discharge manifold (or field installed as specified on plans). Systems with positive inlet gauge pressure shall have a factory installed pressure transducer on the suction manifold for water shortage protection.

Pressure transducers shall be made of 316 stainless steel.

Transducer accuracy shall be +/- 1.0% full scale with hysteresis and repeatability of no greater than 0.1% full scale. The output signal shall be 4-20 mA with a supply voltage range of 9-32 VDC.

E. A bourdon tube pressure gauge, 2.5 inch diameter, shall be placed on the suction and discharge manifolds. The gauge shall be liquid filled and have copper alloy internal parts in a stainless steel case. Gauge accuracy shall be 2/1/2 %. The gauge shall be capable of a pressure of 30% above its maximum span without requiring recalibration.

F. Systems with a flooded suction inlet or suction lift configuration shall have a factory installed water shortage protection device on the suction manifold.

G. The base frame shall be constructed of corrosion resistant 304 stainless steel. Rubber vibration dampers shall be fitted between each pumps and baseframe to minimize vibration.

H. Depending on the system size and configuration, the control panel shall be mounted in one of the following ways:

On a 304 stainless steel fabricated control cabinet stand attached to the system skid.

On a 304 stainless steel fabricated skid, separate from the main system skid On its own base (floor mounted with plinth)

2.10 TESTING

A. The entire pump station shall be factory performance tested as a complete unit prior to shipment. Job-site programming shall be entered into the controller prior to shipment (details of installation requirements shall be communicated to the pump system manufacturer). A verified performance test report shall be made available from the system manufacturer.

B. The system shall undergo a hydrostatic test of 350 psig for a minimum of 15 minutes prior to shipment.