低压通用变频输出电压为380～650V，输出功率为0.75～400kW，工作频率为0～400Hz，它的主电路都采用交—直—交电路。其控制方式经历了以下四代。

其特点是控制电路结构简单、成本较低，机械特性硬度也较好，能够满足一般传动的平滑调速要求，已在产业的各个领域得到广泛应用。但是，这种控制方式在低频时，由于输出电压较低，转矩受定子电阻压降的影响比较显著，使输出**转矩减小。另外，其机械特性终究没有直流电动机硬，动态转矩能力和静态调速性能都还不尽如人意，且系统性能不高、控制曲线会随负载的变化而变化，转矩响应慢、电机转矩利用率不高，低速时因定子电阻和逆变器死区效应的存在而性能下降，稳定性变差等。因此人们又研究出矢量控制变频调速。

它是以三相波形整体生成效果为前提，以逼近电机气隙的理想圆形旋转磁场轨迹为目的，一次生成三相调制波形，以内切多边形逼近圆的方式进行控制的。经实践使用后又有所改进，即引入频率补偿，能消除速度控制的误差；通过反馈估算磁链幅值，消除低速时定子电阻的影响；将输出电压、电流闭环，以提高动态的精度和稳定度。但控制电路环节较多，且没有引入转矩的调节，所以系统性能没有得到根本改善。

矢量控制变频调速的做法是将异步电动机在三相坐标系下的定子电流Ia、Ib、Ic、通过三相－二相变换，等效成两相静止坐标系下的交流电流Ia1Ib1，再通过按转子磁场定向旋转变换，等效成同步旋转坐标系下的直流电流Im1、It1(Im1相当于直流电动机的励磁电流；It1相当于与转矩成正比的电枢电流)，然后模仿直流电动机的控制方法，求得直流电动机的控制量，经过相应的坐标反变换，实现对异步电动机的控制。其实质是将交流电动机等效为直流电动机，分别对速度，磁场两个分量进行独立控制。通过控制转子磁链，然后分解定子电流而获得转矩和磁场两个分量，经坐标变换，实现正交或解耦控制。矢量控制方法的提出具有划时代的意义。然而在实际应用中，由于转子磁链难以准确观测，系统特性受电动机参数的影响较大，且在等效直流电动机控制过程中所用矢量旋转变换较复杂，使得实际的控制效果难以达到理想分析的结果。

1985年，德国鲁尔大学的DePenbrock教授首次提出了直接转矩控制变频技术。该技术在很大程度上解决了上述矢量控制的不足，并以新颖的控制思想、简洁明了的系统结构、优良的动静态性能得到了迅速发展。该技术已成功地应用在电力机车牵引的大功率交流传动上。 直接转矩控制直接在定子坐标系下分析交流电动机的数学模型，控制电动机的磁链和转矩。它不需要将交流电动机等效为直流电动机，因而省去了矢量旋转变换中的许多复杂计算；它不需要模仿直流电动机的控制，也不需要为解耦而简化交流电动机的数学模型。

VVVF变频、矢量控制变频、直接转矩控制变频都是交—直—交变频中的一种。其共同缺点是输入功率因数低，谐波电流大，直流电路需要大的储能电容，再生能量又不能反馈回电网，即不能进行四象限运行。为此，矩阵式交—交变频应运而生。由于矩阵式交—交变频省去了中间直流环节，从而省去了体积大、价格贵的电解电容。它能实现功率因数为l，输入电流为正弦且能四象限运行，系统的功率密度大。该技术虽尚未成熟，但仍吸引着众多的学者深入研究。其实质不是间接的控制电流、磁链等量，而是把转矩直接作为被控制量来实现的。具体方法是：

1、控制定子磁链引入定子磁链观测器，实现无速度传感器方式；

2、自动识别(ID)依靠**的电机数学模型，对电机参数自动识别；

3、算出实际值对应定子阻抗、互感、磁饱和因素、惯量等算出实际的转矩、定子磁链、转子速度进行实时控制；

4、实现Band—Band控制按磁链和转矩的Band—Band控制产生PWM信号，对逆变器开关状态进行控制。

矩阵式交—交变频具有**的转矩响应(<2ms)，很高的速度精度(±2%，无PG反馈)，高转矩精度(<+3%)；同时还具有较高的起动转矩及高转矩精度，尤其在低速时(包括0速度时)，可输出150%～200%转矩。

VVC的控制原理是将矢量调制的原理应用于固定电压源PWM逆变器。这一控制建立在一个改善了的电机模型上，该电机模型较好的对负载和转差进行了补偿。

因为有功和无功电流成分对于控制系统来说都是很重要的，控制电压矢量的角度可显著的改善0-12HZ范围内的动态性能，而在标准的PWM U/F驱动中0-10HZ范围一般都存在着问题。

利用SFAVM或60°AVM原理来计算逆变器的开关模式，可使气隙转矩的脉动很小（与使用同步PWM的变频器相比）。
 

VM2327P23A000 (AP23A000 ACTUATOR WITH VM2327 3/4" 2 WAY VALVE) INVENSYS SCHNEIDE

VB-7263-000-4-04 Siebe Invensys    In Box Valve Body VB7263000404

VALVE ACTUATOR PNEUMATIC MK-4601-0-0-2 MK4601002 INVENSYS   

  INVENSYS SERVICE REGULATOR SERIES 143-80

  INVENSYS K4SS-A0060-010-0-00 CHART RECORDER 110VAC/60HZ,3987T CD

  INVENSYS ConTROL SYSTEM BIEBE ENVIRonMENTAL ConTROLS DMS-ECH-001 CK

  Foxboro Invensys Pressure Transmitter IDP10-A22A11F-M1 MWP @ 3626 PSI

  FOXBORO 210S-1 INVENSYS SPEC 200 INDICATOR BASIC 1POINTER PI-9228,PI-002 CX

  ACCOS CARD 30 GPIC ISS 6 GS2 AS31 A80 INVENSYS ENGINEERING

Uni-Line 2392-504 Pneumodular Selector Relay 2 Position selector switch Invensys

TSMN 90221 850 ROOM TEMPERATURE SENSOR - SIEBE/BARBER COLMAN/INVENSYS

TS-5751-850 OUTDOOR AIR SENSOR - TAC - INVENSYS -    IN BOX _

TS 8422 (same as TS 9422) TEMPERATURE SENSOR - INVENSYS/SIEBE/BARBER COLMAN/TAC

Traub TD Spindelmotor INVENSYS Typ.WU-DA112 MS Motor Elektrik

Thermostat Pneumatic 2212-119 Invensys    In Box

THERMOSTAT BARBER COLMAN TK-1001-0-2 TK100102 INVENSYS DIRECT PNEUMATIC ROOM   

THERMOSTAT ; GS , 3/8 X 5-3/8, 30 for Pitco, Part # P5047588 , Invensys

Thermocouple Invensys 350475 MG21-2668 Control   

TARGET / INVENSYS SENSOR SYSTEMS VARIABLE RESISTOR PART # 18-37904B01 (200WS307)

TACO/SIEBE/INVENSYS ERIE POPTOP FLOATING N/O VALVE ACTUATOR AT23A00T 24VAC +_

TACO INVENSYS SCHNEIDER ELECRIC IA MNL 800 101 LON CARD

TAC SIEBE INVENSYS MN-FLO3T Micronet VAV Controller

TAC SIEBE INVENSYS MN-FLO3T Micronet VAV Controller

TAC SIEBE INVENSYS MN-FLO Micronet VAV Controller

TAC SIEBE INVENSYS MN-FLO Micronet VAV Controller

TAC Invensys Barber Colman 2376-501 Pneumodular Averaging Relay    in Box!

TAC - Invensys Part # RYB-9213-101-0-16 - Removable Seat Ring for VB-9xx3-0-5-16

TAC - Invensys Part # NYB-7213-102-0-8 SE-SUBMCH 1" N.O. Valve Body Bonnet

T.A.C., Invensys, VB-7211-000-4-06, Straight Mount, Two Way Valve Body

T.A.C., Invensys, 21-957, Thermostat Cover

T.A.C. INVENSYS BARBER COLMAN DUCT HUMIDISTAT HC-201    HC201

T.A.C. / Siebe / Invensys MK-4621-0-0-2 Pneumatic Valve Actuator

SWICHTEC INVENSYS ENERGY MAIN POWER BOARD 350-00079-01D DRG 21135 FOR R5800 ILPS

SWICHTEC INVENSYS ENERGY DRG 21592 CIRCUIT BOARD 350-00079-18B R5800 LCD DISPLAY

SWICHTEC INVENSYS ENERGY 350-0079-54C R5848-11 RECTIFIER ConNECTOR BOARD

SPARK MODULE, SM2 INVENSYS 120V. 3mA. A10006 - AMERICAN RANGE, BAKERS PRIDE   

SonDE INVENSYS DWT 0001

SM50 Intergy Invensys Supervisory Module

SIM-CCN GCM SIEBE Barber-Colman Invensys Carrier CCN Systems Integration Module

SIEBE PP-2446 PRESSURE TRANSDUCER BARBER COLMAN TAC INVENSYS ERIE

Siebe MSC-P-751 Environmental Controls Controller (Invensys?)

Siebe MSC-P1504-D Controller Lev-11 w/ AO & clock invensys robertshaw

Siebe MSC-NCM-D Controller invensys robertshaw

Siebe MSC-NCM Network Controller W/Modem MSCNCM Invensys

SIEBE INVENSYS MPC-8AI HVAC CONTROL, MULTI-PURPOSE CONTROLLER, ANALOG INPUT - US

SIEBE INVENSYS MPC-4A0 MULTI-PURPOSE CONTROLLER, ANALOG OUTPUT MODULE -   w/G

Siebe Invensys MK-2690-0-0-2 VKS-9263-203-4-35 Actuator Valve Stainless Steel

Siebe GCM SIM-York GCM-86000 York Talk Invensys TAC Network 8000

SIEBE BARBER COLMAN INVENSYS 1/2" NPT 3-WAY ConTROL BLEND VALVE VS-9313-201-4-4

SIEBE BARBER COLMAN INVENSYS 1/2" NPT 2-WAY ConTROL BLEND VALVE VK-9211-201-4-3

Siebe Barber Coleman Invensys VK-7213-201-4-01 Valve Assembly 1/2" reduced port

Sensus Invensys ICE 5/8" by 5/8" Water Meter SRII BRAND   

SEALED   ! LAMBDA / INVENSYS POWER SUPPLY SE-500-3 SE5003

Scotsman Water Valve for CM250 120V 50/60hz 10W Invensys S-30 K-63916-12

Scotsman Water Valve 24V 60HZ 10W Invensys S-53N 283H11 K-67953

Scotsman Water Valve 24V 60HZ 10W INVENSYS K-76858

Scotsman 12-2548-01 Water Valve 24V 60HZ 10W Invensys 12-2548-01c

Schneider TAC Invensys Unit Ventilator Thermostat 2298-060    In Box

Schneider Invensys MP-495-0-2-2 Actuator 120V 50W .95A MP495022 50/60Hz

SCHNEIDER ELECTRIC, INVENSYS, TAC MN 150 LON CONTROLLER, SAT3 W/ROOFTOP PROFILE_

SCHNEIDER ELECTRIC, INVENSYS TAC MNL-V3R VAV ConTROLLER VAV MNL-V3RV2 PROFILE +_

Schneider Electric Invensys modulating valve AT13A00T Erie Pop Top

Schneider Electric Invensys diverting relay 4-20 PSIG set point 2325-502

Safetran Invensys DC to DC Converter A53106 9000-53106-0001 Rev E3

RX-19-36 ROBERTSHAW / INVENSYS FRYER THERMOSTAT FOR MILLIVOLTS RX1936 RX 19 36

ROTAVAL STAINLESS FEEDER W/ INVENSYS(.90HP) MOTOR AND RADICON GEAR  

Robertshaw Invensys Valve Model #P2

Robertshaw Invensys Range Temperature Dial Knob #4590-004

ROBERTSHAW INVENSYS MG21-1126 PRESSURE ConTROL (R2-4-24KD)

ROBERTSHAW INVENSYS GIST 100 - 320°C GRIDDLE THERMOSTAT GAS VALVE WITH IGNITION

Robertshaw Invensys Gas Thermostat,for Vulcan,Garland,Southbend #BJWA 25PC1-536

Robertshaw Invensys Gas Thermostat,3/8" FPT, #46-347

Robertshaw Invensys FD0-3-02-54 Gas Thermostat Model FD0, 461128 GARLAND   

Robertshaw Invensys Electric Thermostat,25A,250VAC,Max 325*F, #KP-87-60

Robertshaw Invensys Electric Thermostat KXT-466-36 175 to 500 Degree

Robertshaw Invensys Electric Thermostat KX-289-30 100 to 450 Degree

Robertshaw Invensys Electric Thermostat KX-289-30 100 to 450 Degree

Robertshaw Invensys Electric Thermostat 5110-052

Robertshaw Invensys Electric Oven Thermostat,30A,277VAC,Max Temp 325*F, #S-476-4

Robertshaw Invensys Electric Oven Thermostat,30A,277VAC,Max 450*F,#S-100-48

Robertshaw Invensys EA5-484-72 Electric Thermostat 180 degree max TST2528

Robertshaw Invensys Dual Solenoid Valve 3/8" FJT 120V #00497639-000G1

robertshaw invensys apl control. MC-20-1101 gard-pak III

Robertshaw Invensys Add-On Stuffing Box Kit For Capillaries #4650-001

Robertshaw Invensys 9920I Thermostat Heat Pump

Robertshaw Invensys 9801I Thermostat Gas Electric Oil Heat Pump

Robertshaw Invensys 9560 Thermostat Heat Pump

ROBERTSHAW INVENSYS 9025i REMOTE OUTDOOR SENSOR

Robertshaw Invensys 9020I Remote Sensor Indoor Use

Robertshaw Invensys 8625 Thermostat Gas Electric Oil Heat Pump

Robertshaw Invensys 8425 Thermostat Gas Electric Oil Heat Pump

Robertshaw Invensys 8401 Thermostat Gas Electric Oil Heat Pump

Robertshaw Invensys 700-705 Energy Cut Off Switch HT3 E

RobertShaw Invensys 60 to 250*F Electric Thermostat Assembly #5300-615

Robertshaw Invensys 41-1402 Hot Surface Furnace Ignitor

Robertshaw Invensys 41-1090 Hot Surface Furnace Ignitor Universal Kit

ROBERTSHAW GAS FRYER THERMOSTAT RX-1-36 MILLIVOLTS INVENSYS CATERING SPARES

Robertshaw Electric Thermostat S-224-24 5300-014 5300-01D 400 Degree Invensys

Robertshaw 5459-074 Invensys Thermostat BNP-404-64 BTP-404-60 288153

Robertshaw 5225-06G High Limit 440F/227C Thermosta Invensys LCC770240000   

Robertshaw 4020-007 Gas Safety Valve FMDA Invensys

Robertshaw 4020-005 Gas Safety Valve FMDA Invensys

Robert Shaw Thermostat Invensys 100-550°F - D1320605900

Robert Shaw / Invensys Gard-Pak 2 Solid State Motor Protector 3433-046

RELAY ELECTRIC PNEUMATIC HVAC INVENSYS 2364-211 R471-1    IN THE BOX

Reduzierung Typ EATON (INVENSYS) Durchflussrate 5,5l/min Druckbereich 1-10bar

RECEIVER ConTROLLER 2341-501 INVENSYS    IN THE BOX

Ranco Invensys L30-83 Solenoid Coil 24 VDC for V1-V12 Reversing Valve Heat Pump

Ranco / Invensys A30-181, ADAPTABLE REFRIGERATOR CONTROL

R2948 Intergy Invensys Rectifier Module

PROV-GCM Proview Programmer/Operator Keypad MMI Invensys Barber-Colman Siebe TAC

Pneumodular Diverting Relay Robertshaw Or Invensys 2353-501    In The Box

Pneumodular Diverting Relay Robertshaw Or Invensys 2353-501    In The Box

Pitco P5047588,Vulcan 410837-1, Invensys GSA60301800, Gas Thermostat 66-1017   

PEM-1 Invensys Barber Colman Siebe Packaged Equipment Module

PEM 1 BARBER COLMAN SIEBE INVENSYS TAC NETWORK 8000 PEM-1 PEM1 _

PEM 1 - BARBER COLMAN NETWORK 8000, SIEBE, INVENSYS, TAC

Peco/T.A.C./Invensys/Schneider Elec - TA-168-9 Manufacturer discontinued GREAT!!

P0917LYFPS40024 - FOXBORO - P0917LY FPS400-24 INVENSYS POWER SUPPLY  

ORIGINAL AC POWER ADAPTER FOR INVENSYS WonDERWARE KonTRON TUOCH PLANEL

NOS! INVENSYS DC TO FREQUENCY ConVERTER 7500-5016-1 750050161

NOS Invensys Valve Body 2-Way VB-7213-0-4-08 VB-7213-000-4-8 1" 14 CV

NOS Invensys Schneider Electric Valve linkage for Gear Train Actuators AV-390

NOS INVENSYS ConTROLS 10-250 SHANK EXTENSION 2"

NOS INVENSYS 2374-498 AIR SENSING SWITCH RSS-498

NIB Invensys Local Control Module base Assembly LCMA 104-1-0-1 Barber Colman

  ! Ranco Invensys 13109 Motor Actuator 127-00022-001 (128) 12V 1/2"

  ! Invensys APV Actuator SW43T10A1E5 Divert Valve

   Whitton Brook Invensys Crompton Fuel Pump & Motor A-EF180MZ-D 8004-1064

   Thermostat by INVENSYS S-112-18 5300-09H 125 VA 120-270 VAC MT 400 F

   TAC INVENSYS PNEUMATIC ACTUATOR VALVE linkAGE KIT MK-2690 AV-400-0-0-1

   TAC Invensys MMC-420 Actuator Control Modules

   STATE-A.O. SMITH 9000547005 GAS ConTROL VALVE*INVENSYS/ROBERTSHAW

   SIEBE AT-523-11-1 RELAY REPAIR KIT INVENSYS BARBER-COLMAN

   Schneider Invensys Barber Colman Diaphragm Actuator MK Series 6" x 4.5"

   ROBERTSHAW INVENSYS MINI-GARD PRESSURE ConTROL MG20-1098 MPL-7003 3100-051

   Robertshaw Invensys INT-43 10-546 Add-A-Wire Thermostat Wiring Adapter

   ROBERSHAW-INVENSYS VS 4010-001 SAFETY VALVE-COMMERCIAL*FMC*NLA/Obsolete

   Overstock Invensys Controls Heavy Duty Refrigerant Hose 48" 1290132-B48

   Overstock Invensys Controls Heavy Duty Refrigerant Hose 36" 1290132-B18

   Overstock Invensys Controls Heavy Duty Refrigerant Hose 24" 1290132-B24

   Overstock Invensys Controls Heavy Duty Refrigerant Hose 18" 1290132-B18

   Open Box INVENSYS 3PSI-15PSI GAUGE 250-3074

   OLD INVENSYS PRESSURE TRANSMITTER 0-6IN H2O 863DPM2D1NKMP FOXBORO GG

   listing    Invensys RKS-2001-0-1 Receiver Controller.   

   listing    Invensys Foxboro D0135ND Electric Level Sensor ORIGIN 2A8716 C0-NI G/M

   listing    Foxboro P0916FL Rev C 32ft Length Cable I/A Series PLC Invensys PO916FL 32'

   listing    Foxboro P0916DY Rev B 32ft Length Cable I/A Series PLC Invensys PO916DY 32'

   listing    Foxboro P0916DE Rev C 32ft Length Cable I/A Series PLC Invensys PO916DE 32'

   listing INVENSYS TC-4252 ELECTRIC BULB THERMOSTAT 2 STAGE M & M CONTROL

   listing Invensys Barber Colman CP-8552 Transducer

   listing Invensys Auxiliary Switch Kit - 2 Spot Switches -   !

   listing Foxboro P0916FL Rev C 18.5ft Length Cable I/A Series PLC Invensys PO916FL 18.5'

   listing Foxboro P0916FK Rev C 18.5ft Length Cable I/A Series PLC Invensys PO916FK 18.5'

   listing Foxboro P0916FK Rev B 18.5ft Length Cable I/A Series PLC Invensys PO916FK 18.5'

   listing Foxboro P0916FJ Rev C 10ft Length Cable I/A Series PLC Invensys PO916FJ 10'

   listing Foxboro P0916DX Rev B 18.5ft Length Cable I/A Series PLC Invensys PO916DX 18.5'

   listing Foxboro P0916DE Rev C 32ft Length Cable I/A Series PLC Invensys PO916DE 32'

   listing Foxboro P0916DD Rev C 18.5ft Length Cable I/A Series PLC Invensys PO916DD 18.5'

   listing Foxboro P0916DD Rev B 10ft Length Cable I/A Series PLC Invensys PO916DD 10'

   listing FOXBORO ECKARDT INVENSYS 139PP-ASEC5 PNEUMATIC PRESSURE REPEATER   

   listing Eurotherm Invensys Barber-Colman Ea22 120v Actuator

   listing BARBER COLMAN SIEBE INVENSYS TAC NETWORK GCM - 86120

   INVENSYS-ROBERTSHAW VC 4220-013 COMMERCIAL OVEN THERMOSTAT*NLA/OBSOLETE

   INVENSYS-ROBERTSHAW 700-101 MANUAL GAS VALVE

   INVENSYS-ROBERTSHAW 5225-005 HI-LIMIT W/RESET*LCH/490F

   INVENSYS-ROBERTSHAW 4350-128 COMMERCIAL GRIDDLE THERMOSTAT*BJWA

   INVENSYS-ROBERTSHAW 4200-512 FDO THERMOSTAT*NLA/OBSOLETE

   INVENSYS-ROBERTSHAW 1720-709 TS MAG HEAD*1/8"FPT PILOT IN & OUT*NLA/OBSOLETE

   INVENSYS-RANCO O12-1505 COMMERCIAL DUAL PRESSURE CONTROL/SPST

   INVENSYS/ISOMAX DX DX1.621.K723L PNEUMATIC SOLENOID VALVE

   INVENSYS/ RANCO 12V MOTOR ACTUATOR/ 3-PORT ELECTRIC WATER VALVE HVAC

   Invensys VK-7313-202-4-4 Valve Assembly 1/2'' Full Port 3-Way 4.4CV

   INVENSYS VB-7253-000-4-10 250PSI 1-1/2IN NPT 2-WAY GLOBE VALVE D419343

   INVENSYS VB-7213-000-4-06 VALVE BODY 3/4''

   INVENSYS TS-8201-106-0-1 SOLID STATE DUCT IMMERSION 4" PROBE

   Invensys Thermistor Room Sensor TS-5711-853

   INVENSYS TEMPERATURE SENSOR TS-90230-850-0-1 TS9023085001 CLASS 2 TEMP

   Invensys Solid State Actuator Drive CP-8301-24-1 -24v/50/60

   INVENSYS SOLENOID VALVE S 3420/00 S342000 24V 5VA

   INVENSYS S-224-24 5300-01D S22424

   INVENSYS PO500SC-D FBM08 INTERFACE MODULE D366198

   INVENSYS PNEUMATIC ROOM TRANSMITTER TKS-5001 TKS5001 50-100°F

   INVENSYS PNEUMATIC HUMIDITY TRANSMITTER HKS-2033-0-2 HKS203302 10-90% RH

   INVENSYS PCUC30P72AI SENSOR

   INVENSYS N800-555-P POS.POSITIONER/linkAGE KIT 5-10PSI D444899

   INVENSYS MP-371-600-0-2 ACTUATOR

   INVENSYS MP-2150-500-2-2 120V ACTUATOR WITH ACTUATOR DRIVE

   INVENSYS MA-5213-0-0-4 hydraulic actuator 24 v. 2 position NOS

   Invensys MA-5213-0-0-4 Actuator

   Invensys MA-418-0-0-3 Two Position Spring Return Actuator MA418003

   INVENSYS M727P411443 IMPELLER NUT FIXING PIN D225139

   INVENSYS INTERMITTENT PILOT IGNITON ConTROL 24VAC LOCKOUT TIMING 780-845!

   Invensys Honeywell Relilative Humidity Pneumatic Thermostat 2230-018 H18-301

   INVENSYS HC-201 HUMIDISTAT 120/240V-AC 345VA HEATING AND COOLING D269900

   INVENSYS H18-301 PNEUMATIC ROOM HUMIDISTAT D420224

   Invensys GCM-ECH-001 Echelon Network Interface Module For GCM-86000 LON

   Invensys G23 High Pressure Control Kit 3126/3127 G23-5052 AP27-4014

   INVENSYS FOXBORO FBM03A I/A SERIES INPUT INTERFACE MODULE D366207

   INVENSYS FOXBORO EVO 2014 RESTORE MEDIA FOR MODEL H92 STYLE G (HP Z420)

   Invensys Foxboro D0135ND Electric Level Sensor ORIGIN 2A8716 C0-NI G/M

   INVENSYS FOXBORO 0-125PSI PRESSURE TRANSMITTER IGP10-A33D1C

   INVENSYS Flow Valve K-12930-1 120V AC for Ipso 209/00026/001

   Invensys Erie 2 POSITION On/Off Valve Body Valve Stem Rebuild Kit 100-083

   INVENSYS ECKARDT LEXG J PNEUMATIC VALVE BLOCK

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