Description
AVR MARELLI M16FA655A
Điều áp Marelli M16FA655A
APPLICATION:
The voltage regulator type “MARK V”, is suitable for Synchronous Generators of MARELLI MOTORI make, MJB series, size range 160-250 frames. The regulator is fully insulated in order to maintain high reliability also with severe ambient conditions (high level of humidity, dust, salt atmosphere), and in case of high vibrations level. The regulator is proper both for single and 3-phase generators.
TECHNICAL SPECIFICATION:
Power supply voltage
(±10% of range tolerance, 50/60Hz) |
170÷277 V |
Voltage sensing (single-phase)
(±10% of range tolerance, 50/60Hz) |
170÷277 V |
Maximum continuative field current | 5 A |
Maximum forcing field current
(1 minute) |
8 A |
Maximum field voltage | 100 V |
Field resistance | 8 W ÷ 20 W |
Regulation accuracy
(steady state conditions, rated, balanced and non deforming load, constant frequency) |
±0.5 % |
Thermal Drift
(% voltage change for 50°C change from Tamb, after 10 minutes) |
±0.5 % |
Response time | 1 cycle |
Operating temperature | -30°C / +70°C |
Weight | 320 g |
FUNCTIONS:
Protection | Under-frequency limiter |
Over-excitation limiter | |
Internal fuse, replaceable | |
Control | With external potentiometer, 100 kΩ 1 W for ∆V = ±5 % of the rated voltage |
With external DC voltage signal (0-10 V) |
TERMINALS:
Connection terminals are performed through FAST-ON terminals. The terminals have to be connected according the applicable wiring diagram, in order to avoid any possible mistake in the wiring.
POTENTIOMETERS:
-VOLT: Potentiometer for adjusting the output voltage of the generator. Normally the internal potentiometer VOLT allows possibility of adjusting the voltage in a wide range; to obtain a finer possibility of voltage setting or to adjust the voltage from the control panel, or in order to limit the voltage range, an external potentiometer can connected to the terminal P and Q (resistance about 100 k, 1 W, to obtain voltage regulation of ±5%).
-FREQ – potentiometer for changing the low speed protection corner frequency. It is usually set at the factory in order to reduce the excitation when speed becomes lower than 90% of rated speed at 50 Hz (frequency lower than 45 Hz, or corner frequency). By removing the bridge which normally shorts the terminals Hz and 60, the speed protection acts properly for 60 Hz operation.
-FREQ – Increases the corner frequency
-STAB – Stability potentiometer: clockwise rotation permits to increase the regulation stability (the response time becomes larger).
-AMP – potentiometer for changing the over excitation limiter; that limiter permits to protect the generator in case of over excitation
Even if correctly set, this function does not substitute external systems protections, it is only a completing device.
STABILITY SETTING:
The voltage regulator is provided with internal adjustable stability circuits in order to allow stable operation in a wide
range of applications. The operation of the regulator can be set on field to adapt it to the characteristics of the plant and of the driving engine (diesel engine, water turbine, gas turbine) in order to obtain the best voltage response.
To change the stability characteristics of the regulator, it is necessary to act on the potentiometer STAB.
OVER-EXCITATION PROTECTION:
in case of over-excitation due to load conditions that could cause the rotor damage. The protection is delayed to avoid transitory conditions and operates by decreasing excitation and keeping it to a safety level.
To change the over-excitation threshold of the regulator, it is necessary to operate with the potentiometer AMP.
EXTERNAL POTENTIOMETERS:
An external potentiometer for fine setting of the voltage reference can be connected to the terminals P and Q.
This permits to:
– Change the voltage set-point by means of remote control device;
– Set the generator voltage reference with accuracy higher than the one of the internal regulator potentiometer VOLT.
EXTERNAL POTENTIOMETERS SPECIFICATIONS ARE THE FOLLOWING:
Setting range Potentiometer specifications
±5% | 100 kΩ – 1 W minimum |
±10% | 200 kΩ – 1 W minimum |
As soon as the external potentiometer is connected to P and Q, a change in the global voltage reference of the regulation
system will occur; the internal trimmer VOLT must be set again to the rated generator voltage.
In detail: put the external potentiometer cursor in mid position, and after that, turn VOLT counterclockwise until to reach approximately the desired generator voltage.It’s now possible to operate the fine setting of the voltage by means of the external potentiometer.
SPECIAL CONNECTIONS: external DC voltage signal:
In particular cases, it is possible to connect to P and Q an external device capable to provide a DC voltage signal to the regulator for generator excitation control.
This signal must be within the range 0 to +10 V (with P positive terminal and Q negative terminal).
WARNING: the external device output connected to P and Q must be galvanically insulated.
It is now possible to control the generator excitation by means of the voltage provided to P and Q; that control is
approximately linear within the following range:
ΔVext | ΔVgen |
+3 V | -20% |
-3 V | +20% |
Hiệp –
sản phẩm tốt, chất lượng.