The Be142 continuously monitors the status of the MAINS. The Be142 allows you to set low/high limits for Mains Voltage and low/high limits for the Mains Frequency. When the voltage and the frequency are within the limits, the Be142 AMF controller transfers the load to the Mains. The Be142 is a full 3-Phase monitoring controller. In cases where a single-phase generator is used we recommend that you consider the Be42 AMF controller:


If the voltage drops below the lower limit (or rises above the high limit) or, if the frequency drops below its limit (or rises above its limit), the Be142 will disable the Mains circuit breaker. This prevents, after a programmable delay, severe damage to your load. So, we can say that Be142 prevents, in the first place damage to your systems. Then, if the failure persists for a long time (a programmable timer is available ranging from seconds up to hours) the Be142 will take care to start your emergency generator. Once again the Be142 does its business to check the quality of the generator voltage and frequency. Once the parameters are within the programmed limits, the BE142 will enable the generator circuit breaker. Now, in case of prolonged power outages, your load is safely supplied by your emergency generator. Be142 as we understood before does not forget to pay attention to the Mains. So, when the Mains parameters will return within the programmed settings, the Be142 AMF controller will transfer the load to MAINS. This will happen after a delay that will ensure that the Mains is in stable conditions. Once your load is connected to the Mains, the engine will run for a programmable time off-load. After that,  the engine will stop and the BE142 is ready for a new power outage.






This is the typical BE142 control panel circuit diagram. You can observe the connections of the current transformers wired on the load side. This allows the Be142 to display the current when a circuit breaker is closed. So, you can read the current into the load even when connected to the power utility. You can set up alarms (warning or shutdown) in case of an over-current. The Be142 will trigger the alarm only when connected to the generator. It is obvious that you can set up all other important protections about Over/Under frequency, voltage, and so on. By adding only a few relays you can interface with all kinds of engines: gas-gasoline-diesel. You can observe the RS485 connection as well. This will allow you remote control monitoring via MODBUS, TCP-IP, or, by using the BE16 module, to GSM systems. The Be142 is designed to drive two contactors. A best practice, in addition to the electrical interlock, is to use a good mechanical interlock. This will avoid back-feeding in case of damage to the Be142 controller. You can connect analog or digital sensors directly to the Be142 inputs. The output of the Be142 is suitable for automotive relays 12V or 24V (according to the battery of the engine). The Be142 outputs are short circuit proof, but we recommend that you connect all the time with flywheel relays.

BE142 wiring diagram
The Be142 is a 3-phase AMF controller. All parameters, alarms, and operating functions are indicated by means of a high-luminosity display. The AMF controller Be142 interfaces with resistive or digital sensors. It measures Vac, Aac, Vdc, Hz, hour count, R.p.m., Oil Pressure, Engine Temperature, Battery Vdc and Fuel Level. Software for remote monitoring is also provided free of charge. The Be142 provides MODBUS via RS485. The AMF controller Be142 complies with NFPA-110 / NFPA-99. By using our TCP-IP server you can monitor and control the Be142 via INTERNET. Option for remote control by GSM is also provided. We provide support to make your own AMF Control Panels.


Push the button [OFF] to enter the OFF mode. The OFF mode clears the fault alarms and allows you to read or program parameters. The Display and LEDs are turned off and a dot on the display will blink slowly. Push one of the pushbuttons on the front panel to energize the display.


Note: default programming for input #36 (Emergency input) is ‘normally closed ‘. To inhibit the alarm  [Er.08], you are required to connect terminal #36  to the ground (Emergency input). The MANUAL mode allows manual control of the engine and circuit breakers.
Push the [MAN] push button to select the MANUAL mode. Push the [START] push button until the engine starts; the display indicates the message [. . . .] during the starting attempts or [! ! ! !] if preheat has been programmed.
When the engine is running, the green LED turns on. To stop the engine, push the [STOP] push button until the [StOP] message appears on the display. If the engine has already stopped, it is possible to reset the STOP sequence by pressing the [STOP] push button.



Select the MANUAL mode, start the engine (see above) and wait for voltage presence. Push the [ I ] (KG) push button to close the Generator circuit breaker. To transfer the Load to Mains, push the [I] (KM) push button (the [KG] will open).  To open a Contactor, push the [O] push button. In manual mode, the CHANGEOVER timer lasts one second.



Note: default programming for input #36  (Emergency input) is ‘normally closed ‘. To inhibit the alarm [Er.08] you are required to connect terminal #36 to the ground (Emergency input). Push the [AUTO] push button until the green LED illuminates. The engine starts when the Be142 detects a Mains failure. The Contactor of the MAINS (KM) opens after the BREAKER timing. After the warm-up time, if the voltage and frequency are within the settings, the circuit breaker of the generator (KG) will close. If the Mains restores, the KG will open. The KM will close following a programmed changeover timing. The Engine will stop after cooling downtime. If the engine shuts down, the KM closes independently of the Mains status if the [P.48] is [ON] (NFPA-110 mode), otherwise, the KM will close only if the Mains is within programmed settings. In AUTO mode, the Be142 will periodically test the engine if the parameters [P.41] and [P.42] have been programmed. During this test, the green LED of the AUTO mode will continue to blink. In AUTO mode, the Be142 can start and stop the engine according to programmed inputs.



Push the [TEST] push-button until the green LED illuminates. The Be142 starts the engine and transfers the load to the Generator if [P.17] is [on]. To stop the engine, select the AUTO mode (if Mains is present) or select the OFF mode. If you push the [STOP] push-button when the Be142 is in AUTO or TEST, the [Er.09] will energize. To clear the alarm, select the OFF mode.


Zona Industriale, 46035 Ostiglia Italy

0039 335 70 77 148


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