1. Manuals
  2. Brands
  3. Stamford Manuals
  4. Controller
  5. MX341 AVR
  6. Manual

Stamford MX341 AVR Manual

Automatic voltage regulator
Hide thumbs

Advertisement

Table of Contents

MX341 Automatic Voltage Regulator (AVR)
SPECIFICATION, CONTROLS AND
ACCESSORIES
English
Original Instructions
A043Y699 (Issue 2)

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the MX341 AVR and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Related Manuals for Stamford MX341 AVR

Summary of Contents for Stamford MX341 AVR

  • Page 1 MX341 Automatic Voltage Regulator (AVR) SPECIFICATION, CONTROLS AND ACCESSORIES English Original Instructions A043Y699 (Issue 2)
  • Page 2 Table of Contents DESCRIPTION ........................SPECIFICATION ........................CONTROLS........................... ACCESSORIES........................A043Y699 (Issue 2)

  • Page 3: Description

    Description Separately-Excited AVR Controlled Alternators 1.1.1 Permanent Magnet Generator (PMG) excited - AVR controlled alternators WARNING Strong Magnetic Field The strong magnetic field from a permanent magnet generator (PMG) can cause serious injury or death by interference with implanted medical devices. To prevent injury, do not work near a PMG if you have an implanted medical device.

  • Page 4: Specification

    Specification MX341 Technical Specification • Sensing Input • Voltage: 190 VAC to 264 VAC 1 phase, 2 wire • Frequency: 50 Hz to 60 Hz nominal • Power Input • Voltage: 140 VAC to 220 VAC 3 phase, 3 wire •...
  • Page 5 • Input resistance 1 kΩ • Quadrature Droop Input • 10 Ω burden • Maximum sensitivity: 0.07 A for 5% droop, zero power factor • Maximum input: 0.33 A • Over-Voltage Detection • Set point: 75 VDC • Time delay: 10 s (fixed) •...

  • Page 6: Controls

    Controls DANGER Live Electrical Conductors Live electrical conductors can cause serious injury or death by electric shock and burns. To prevent injury and before removing covers over electrical conductors, isolate the generator set from all energy sources, remove stored energy and use lock out/tag out safety procedures.
  • Page 7 Ref. Control Function Turn potentiometer CLOCKWISE to AVR [VOLTS] Adjust alternator output increase voltage voltage Link : Hand trimmer Adjust alternator output increase voltage voltage 1-2 : Not fitted None : Fitted AVR [STAB] Adjust stability to prevent increase damping effect voltage hunting Link : Power Select stability response...
  • Page 8 AVR [EXC] Adjust over-excitation increase trip excitation voltage protection FIGURE 1. MX341 AVR CONTROLS Initial AVR Setup NOTICE The AVR must be setup only by authorised, trained service engineers. Do not exceed the designed safe operating voltage, shown on the alternator rating plate.
  • Page 9 3. Check that the remote hand trimmer is fitted or terminals 1 and 2 are linked. NOTICE If a remote hand trimmer is connected, set it to 50%, the midway position. 4. Turn the AVR [STAB] control to 50%, the midway position. 5.
  • Page 10 5. Verify that the alternator voltage is within safe limits. NOTICE If the voltage is unstable go immediately to step 5. 6. Adjust the AVR [STAB] control slowly counter-clockwise until the output voltage becomes unstable. 7. Adjust the AVR [STAB] control slowly clockwise until the voltage is stable. 8.
  • Page 11 8. Adjust the AVR [UFRO] control slowly clockwise until the AVR LED is just OFF. NOTICE Do not go past the point at which the LED is just OFF. 9. Adjust the alternator speed back to 100% nominal. The LED should be off. The AVR [UFRO] control is now set.
  • Page 12 An analog input (-5 VDC to +5 VDC) modifies the AVR excitation voltage, by adding to, or subtracting from, the sensed alternator voltage. A Stamford Power Factor Controller (PFC3) can provide such an input. The AVR [TRIM] control adjusts the effect.
  • Page 13 The AVR protects the alternator by removing excitation if it senses that the excitation voltage exceeds a threshold set by the AVR [EXC] control. 1. If the excitation voltage exceeds the over-excitation trip setting, the red LED on the AVR turns on. 2.

  • Page 14: Accessories

    4.1.2 Description The STAMFORD Alternator Protection Module (APM) is a three-phase over-voltage/under- voltage detector. The APM detects if any phase-to-neutral voltage exceeds an adjustable upper threshold or falls below a fixed lower threshold, and switches an internal relay if the fault persists for more than a few cycles (to avoid nuisance activation).
  • Page 15 Key features include: • Robust and reliable solid-state electronics • Built-in relay to operate a protective circuit • Short circuit protection without current transformers • Simple connection to the alternator. 4.1.3 Specification • Input • Voltage: 100 VAC to 360 VAC, 50 Hz to 60 Hz, 1 phase or 3 phase + neutral (APM 220 VAC version) •...
  • Page 16 Ref. Control Function Turn potentiometer CLOCKWISE to THRESHOLD Adjust over-voltage threshold increase voltage to operate relay Sensing Input Connect to alternator output U, V, W, N Output relay contacts Connect to external control system L, W : FIGURE 3. ALTERNATOR PROTECTION MODULE CONTROLS A043Y699 (Issue 2)
  • Page 17 Diode Failure Detector 4.2.2 Description The STAMFORD Diode Failure Detector (DFD) senses ripple current in the exciter output caused by diode failure in short or open circuit, and switches an internal relay if it persists for 7 seconds. The changeover contacts of the relay can be wired to provide a warning indication of diode failure or initiate an automatic shutdown.
  • Page 18 • Voltage: 200 VAC to 280 VAC • Current: 0.2 A maximum • Output • Single pole changeover relay rating: 5 A @ 30 VDC, 5 A @ 240 VAC • Isolation: 2 kV • Volt-free contacts • Time Delays •...
  • Page 19 Ref. Control Function Link : Test Test DFD function T1-T2 Sensing Input Connect F2 in series between exciter stator and AVR XX, XX Output relay contacts Connect to external warning or shutdown system 11-14 : Normally-open 11-12 : Normally-closed Link : Supply voltage Select VDC or VAC supply voltage COM-DC : 12 VDC to 28 VDC COM-120 : 100 VAC to 140 VAC...
  • Page 20 The ELM has been specially designed for use with all Stamford AVRs. It is powered independently from the engine battery at 12 VDC or 24 VDC. It operates by detecting the absence of the characteristic ‘rectifier ripple’...
  • Page 21 • Power Input • Voltage: 10 VDC to 14 VDC (ELM 12V version) • Voltage: 20 VDC to 28 VDC (ELM 24V version) • Current: 25 mA max. in standby (both versions) • Relay on: 150 mA maximum (ELM 12V version) •...
  • Page 22 Ref. Control Function Turn potentiometer CLOCKWISE to DELAY Adjust time delay increase delay to operate relay Sensing Input Connect to exciter stator F1, F2 Output relay contacts Connect to external control system COM-NO : Normally-open COM-NC : Normally-closed Power Input Connect to engine battery B- : Battery negative B+: Battery positive...
  • Page 23 Frequency Detection Module 4.4.1 Description The STAMFORD Frequency Detection Module (FDM) is used with a separately-excited alternator, deriving an alternator frequency (rotational speed) signal from the Permanent Magnet Generator (PMG). The FDM operates a relay if the frequency falls below an adjustable preset under-frequency threshold.
  • Page 24 4.4.3 Controls DANGER Live Electrical Conductors Live electrical conductors can cause serious injury or death by electric shock and burns. To prevent injury and before removing covers over electrical conductors, isolate the generator set from all energy sources, remove stored energy and use lock out/tag out safety procedures.
  • Page 25 Ref. Control Function Turn potentiometer CLOCKWISE to MODE Select under-frequency relay mode 0 = relay energised at rest 1 = relay de-energised at rest Adjust under-frequency threshold increase frequency to operate relay HIGH Adjust over-frequency threshold increase frequency to operate relay Power Input Connect to engine battery B- : Battery negative...
  • Page 26 Manual Voltage Regulator 4.5.2 Description The STAMFORD Manual Voltage Regulator (MVR) automatically controls alternator current output to a manually-set constant, independent of alternator voltage or frequency. A manually-controlled excitation system can be useful if the AVR fails. Although not practicable for stand-alone operation, a manually-controlled alternator can operate in parallel with another alternator whose AVR is healthy.
  • Page 27 An MVR is used with a separately-excited AVR, and powered from the same permanent- magnet generator (PMG). PMG-powered systems offer reliable build-up and sustained short- circuit current for flexibility and operational stability. Key features include: • Robust and reliable solid-state electronics •...
  • Page 28 DANGER Live Electrical Conductors Live electrical conductors at output, AVR and AVR accessory terminals, and AVR heat sink can cause serious injury or death by electric shock and burns. To prevent injury, take suitable precautions to prevent contact with live conductors including personal protective equipment, insulation, barriers and insulated tools.
  • Page 29 Ref. Control Function Mode Select Switch AUTO : exciter stator current controlled by AVR OFF : zero exciter stator current MANUAL : exciter stator current set by excitation control potentiometer Excitation control Set exciter stator current in Manual mode potentiometer X, XX : exciter stator Connections to AVR P2, P3, P4 : power supply...

  • Page 30: Remote Control Interface

    Description The STAMFORD Remote Control Interface (RCI) is used with a STAMFORD Automatic Voltage Regulator (AVR) or a STAMFORD Power Factor Controller (PFC3) to control the alternator voltage or power factor (respectively) remotely. The RCI has two inputs which accept unipolar 4-20Ma or bipolar 0-10 volt signals to control alternator power factor from 0.7 lag to 0.7 lead or alternator voltage up to +/- 10%.
  • Page 31 • Voltage control: -10% (4 mA) to +10% (20 mA) or -10% (-10 VDC) to +10% (+10 1617 VDC) • Response time constant: less than 20 ms • Environmental • Vibration: 50 mm/s @ 10 Hz to 100 Hz, 4.4 g @ 100 Hz to 300 Hz •...
  • Page 32 4.6.3 Controls DANGER Live Electrical Conductors Live electrical conductors can cause serious injury or death by electric shock and burns. To prevent injury and before removing covers over electrical conductors, isolate the generator set from all energy sources, remove stored energy and use lock out/tag out safety procedures.
  • Page 33 Ref. Control Function Power Supply Connect to VAC supply voltage E0, 115 : 110 VAC to 125 VAC E0, 220 : 200 VAC to 230 VAC E0, 240 : 231 VAC to 250 VAC E0, 277 : 251 VAC to 290 VAC Link : Control Input Select current or voltage control input C-I : current signal...
  • Page 34 Hand Trimmer (for remote voltage adjustment) A hand trimmer can be fitted in a convenient position (typically in the generator set control panel) and connected to the AVR to provide fine adjustment of the alternator voltage. The hand trimmer value and the adjustment range obtained is as defined in the Technical Specification.

Table of Contents

Save PDF