SJE-Rhombus

VFDC-4000 Panel Engineering Specifications

Download VFDC-4000 Panel Engineering Specs Document (rtf format)

I. General
1.1 Scope Of Work
The contractor shall furnish, install and install a pump control system designed to operate ___ (1-4) pump(s) in a water booster application using Variable Frequency Drives (VFDs) as described herein. The control system shall be designed utilizing proven technology in control design for constant pressure water booster stations. The control system shall be operator and maintenance friendly to ensure ease of system set up and to limit down time.

The pump control system shall be capable of operating ___ (1-4) pumps as manufactured by _______________Model______ at ___HP, ___ Voltage, ___ full load amps ( FLA ), ___ 3 phase, 60Hz. The incoming power on site shall be ____Vac, ___phase, 60Hz. The control system shall use a pressure transmitter connected to common discharge piping for all the pumps.

The factory assembled system shall include:

-Variable Frequency Drives
-Line and load reactor as required.
-Pressure transmitter
-Pressure Booster Controller
-Enclosure
-Circuit breakers
-Alarm and Communication interface

These specifications describe model VFDC-4000 control panel as manufactured by
SJE-Rhombus, Detroit Lakes, Minnesota, USA or approved equal.

II. Products
2.1 General
2.1.1 Codes
Electrical equipment, materials and workmanship shall comply with all applicable codes, safety and fire law regulations at the location of the work and shall conform to applicable codes and standards of the organizations listed below.

1. Institute of Electrical and Electronic Engineers. (IEEE)
2. National Electric Code. (NEC)
3. National Electrical Manufacturers Association (NEMA)
4. American National Standards Institute. (ANSI)
5. Underwriters Laboratories. (UL 508)
6. International Electrotechnical Commission (IEC)

2.1.2 Component Standards
All equipment and materials shall be new and shall bear the manufacturers name and trade name. In cases where the standard has been established for the particular material, the material shall be so labeled. The equipment to be furnished shall essentially be the standard product of a manufacturer regularly engaged in the production of the required type of equipment for this type of work and shall be the manufacturers latest approved design.

2.2 Construction
2.2.1 Enclosure
For indoor applications: The described equipment shall be housed in a single NEMA 1 painted steel enclosure. The enclosure shall be sized approximately to allow easy access to component and adequate ventilation for VFDs. The enclosure shall also include louvers, filter fans and air conditioning as required from VFD heat loss calculation and average ambient temperature.

For outdoor enclosures: The described equipment shall be housed in a single NEMA 3R free standing painted steel enclosure. The enclosure shall be sized approximately to allow easy access to component and adequate ventilation for VFDs. The enclosure shall also include louvers, filter fans, air/air heat exchanger, water/air heat exchanger and air conditioning as required from VFD heat loss calculation and average ambient temperature. Additional measure such as mounting the heat sink of the VFD on the outside of the enclosure, painting the enclosure white, installing a sun shield, adding heaters and adding insulation to the inside of the enclosure shall also be considered as to prevent the temperature inside the enclosure to exceed the acceptable VFD manufacturer limits.

2.2.3 Control Circuit Wiring
Control circuit wiring inside the panel shall be 18 gauge (AWG) minimum, type MTW or THW, rated for 600 volts. All power wiring shall be 12 gauge (AWG) minimum rated for 600 volts. Conductors shall be color coded in the same colors throughout the entire panel.

III. Components
Variable Frequency Drive Controller for constant pressure pumping applications. The VFDC-4000 is microprocessor controlled system capable of monitoring the discharge pressure of a pumping system and adjust the speed of each pump as to maintain a constant pressure. The VFDC-4000 is able to control up to 4 Variable Frequency Drives for constant pressure applications. It also built in data logging, communications capabilities and automatic pump alternation functions.

Features:
- 1 to 4 VFDs control.
- P.I.D. control
- Graphic screen display with back light
- System Status display
- Operating pressure
- Set pressure
- Auto / Off
- Time and date
- Alarm with time and date
- Pump status display
- Pumps in use
- Lead pump
- Pump run / stop
- Pump speed
- VFD Fault
- Four arrow keys button for easy navigation and setup
- Automatic alternation
- Cycle based
- Time based
- Alarm log
- Pump run times
- Real time clock
- Scheduled pressure setup function
- Night time operation (runs smaller pump)
- Pressure transmitter setup
- Password protection
- Serial communication
- Idle prevention
- Freeze prevention
- Low pressure alarm
- High pressure alarm
- Low suction pressure / low level

3.1.1 Analog Input
The controller shall come standard with a 4-20mA input channel. The input shall be scalable from 0.0 to 999.9 and the measurement unit shall be selectable from PSI or Bar. The controller shall detect invalid sensor readings and open loop circuit and display a fault message and de-energize the relay outputs. The analog input channel shall have a 0.1% resolution and incorporate noise filtering and averaging.

3.1.2 Digital Inputs
The controller shall come standard with 6 input channels.

1. System in Automatic mode. From selector switch.
2. Low water alarm. From low suction pressure switch or level switch.
3. VFD 1 Fault.
4. VFD 2 Fault.
5. VFD 3 Fault.
6. VFD 4 Fault.

3.1.3 Relay Outputs
The controller shall come standard with 11 relay outputs, each output capable of switching 5A at 250VAC.

1. Run pump 1
2. Reset VFD1
3. Run pump 2
4. Reset VFD2
5. Run pump 3
6. Reset VFD3
7. Run pump 4
8. Reset VFD4
9. Programmable Relay1
10. Programmable Relay2
11. Programmable Relay3

3.1.4 Analog Output
Four optically isolated analog outputs shall be available to control the speed of each VFD.

3.1.5 Pressure Set Points
The pump operation and alarm status shall be dependent on the following pressure set point in the controller.

1. •  Low pressure alarm
2. •  Stop lead pump pressure
3. •  Stop lag pump pressure
4. •  Start lead pump pressure
5. •  Start lag pump pressure
6. •  High pressure alarm

Pressure adjustments shall be accomplished via the front keypad without the use of tools, laptop computer or extensive configuration.

3.1.6 Display / Keypad
The controller shall allow the user to navigate through the configuration mode and adjust set point values via the front keypad. The controller setup shall be simple and shall not require the use of a laptop computer.

3.1.7 Power
The controller shall require 24 VDC for proper operation. Such power supply shall be approved, registered and /or certified by the Underwriter Laboratory (UL).

3.1.8 Manufacturer
The level controller shall be as manufacturer by SJE-Rhombus, model VFDC-4000.

3.2 Pressure Transmitter
The pressure transmitter shall be industrial grade and have a static accuracy better than 1% of full scale. The pressure transmitter shall be two wire loop powered and produce a 4-20mA proportional to the discharge pressure and be fully temperature compensated. The transmitter shall be connected to the pump discharge and shall have an isolation and bleed valve. The connection shall be ½ inch NPT or ¼ inch NPT male and shall be mounted in such a manner as to minimize the possibility of air accumulation between the transmitter and the discharge pipe.

3.3 Communication
The control panel shall be capable of communicating to a building Management System (BMS) via RS 232 or RS 485 port using MODBUS protocol.

3.4 Circuit Breakers
All electrical circuits shall be protected by molded case circuit breakers. Each pole of the breaker shall provide inverse time delay overload protection and instantaneous short circuit protection by means of a thermal magnetic element.

The breaker shall be operated by a toggle-type or rotary handle and shall have a quick make, quick break switching mechanism that is mechanically trip free from the handle. Tripping due to overload or short circuit shall be clearly indicated by the handle automatically assuming a position midway between the manual “on” and “off” position. Breakers shall be completely enclosed in a molded case and shall bear the UL label. The short circuit interrupt capability shall exceed the fault level (Isc) of the incoming power. The circuit breakers for the VFDs shall be mounted on the sub-panel of the enclosure with the operating handles mounted through the door. The handles will interlock with the door mechanism, only allowing the door to open when the breakers are in the OFF position.

3.5 Relays
3.5.1 Relay Type
Relays shall be of the square base plug in type with integral LED indicator lights. All relays shall have a transparent polycarbonate dust cover to protect the contact surfaces from airborne dust and other contaminants. All relays shall have DPDT or 4PDT contacts, as required. Relays shall be rated for continuous duty operation.

3.5.2 Relay Contacts
Relay contacts shall be rated for 10 amps at 300VAC. Relay sockets shall have screw terminals with self-lifting clamps and terminal identification numbers located at each connection on the relay socket.

3.6 Lightning Arrestor/Surge Arrestor
A lightning/surge arrestor shall be provided at the incoming power terminals to the control panel. The unit shall be of the solid state type and be able to clamp in five (5) nanoseconds and absorb up to 25KA peak surge current during an occurrence. The unit shall have a surge life expectancy of 10,000 occurrences at 200 amps.

3.7 Variable Frequency Drives
A variable torque Variable Frequency Drive (VFD) of the pulse width modulated type shall be supplied for each pump to convert single phase power to three phase power and to control the pumps. The VFD shall be sized for the pump motors supplied by the CONTRACTOR and be compatible with all equipment utilized at the lift station. The VFD's shall meet the following requirements:

- Efficiency rating of 95% or better across the full operating speed range.
- Overload current capacity of 120% for 1 minute.
- The VFD shall be sized to the motor Service Factor Amps (SFA) and not the Full Load Amps (FLA)
- Motor overload for instantaneous trip and motor over-current.
- Over-voltage, undervoltage, over-temperature, ground fault, control or microprocessor faults. These faults shall provide an orderly shutdown of the VFD, indication of fault, and require a manual reset (except for undervoltage) before restart. The history of previous faults shall be stored in memory for future review.
- The VFD shall have a display for indication of frequency, motor current and power and a for field adjustments.
- Line voltage variation tolerance up to +10/-15%.

The VFD manufacturer shall provide a 12 month warranty against defects in workmanship and materials under normal use operation and service from the date of startup.

3.8 Line and Load Reactors
A 5% impedance line reactor shall be installed ahead of each VFD as to reduce the effects of current and voltage harmonics. On systems 100HP and up, passive filters of 12 or 18 pulse VFD configuration may be required to keep the harmonics levels with the IEEE 519 specifications.

Each VFD shall require a load reactor if the pump leads exceed 150 ft from the VFD. For leads exceeding 500 ft, a dV/dT filter shall be required to limit the voltage spike and potential long term damage to the motor windings.

IV. Quality Assurance
4.1 Manufacturer Experience
4.1.1. UL Certification
The manufacturer of the control system shall be certified by Underwriters Laboratories (UL) as being a UL 508 listed manufacturing facility and certified to install a serialized label for quality control and insurance liability considerations.

4.1.2 Experience
The manufacturer of the control system must be able to document ten years of experience in successfully designing and manufacturing similar control system using variable Frequency Drives in pumping applications.

4.2 Manufacturer Quality Control
The complete control system shall be functionally tested at the manufacturing facility and certified as a complete system to assure proper operation per specification.

4.3 Manufacturer Approval
Manufacturers listed in this specification do not constitute approval. All controls must have the capabilities and functions as outlined in the specifications.

V. Submittal Requirements
5.1 Base Bid
The base bid control system shall be the VFDC-4000 control system as manufactured by SJE-Rhombus, Detroit Lakes Minnesota. Contract shall be awarded on the base bid control system. Alternative deductive systems will be considered only after contract award and must be specified with any applicable deducts at bid time in order to receive consideration. Bidders submitting alternate quotations shall submit appropriate cut sheets, circuit drawings and a detailed bill of materials with their alternate bid packages. Approval of an alternative system shall be at the sole discretion of the engineer. All equipment and materials shall be new and shall be specifically designed for the function herein.

5.2 Substitutions
The Engineer will consider proposals for substitution of materials, equipment, methods and services only when proposals are accompanied by full and technical data and all other information required by the Engineer for the proposed substitution. Substitution of materials, equipment, methods and/or services is not allowed unless such substitution has been specifically approved by the Engineer.

5.3 Shop Drawing Submittals
5.3.1 Drawing Requirements
All drawings are to be of the computer generated class.

5.3.2 Engineering Approval
The Engineer reserves the right to approve or disapprove any and all equipment during the evaluation process. Approval for fabrication and installation will be made only after submittal and review of all shop contract documents. The information required for approval shall include the following items and be provided in (8) sets as a minimum: