DC VOLTAGE MONITORING RELAY

10-400VDC LOW-HIGH VOLTAGE MONITORING RELAY  -  AUTO START & STOP RELAY

HIGH PRECISION - QUARTZ TIMING ACCURACY  - STATIC OUTPUT  - RAIL MOUNT - USB CONNECTION

When the battery voltage drops below the [VT-] setting, the BE48 energizes the output. You can connect a 12V small relay or you can directly connect the output to the generator AUTO START module input. In this way, the engine will start. Once the battery voltage will rise above the [VT+] setting, the output will de-energize. Consequently, the engine will stop. You can set timers to delay the start [T1] or to delay the stop [T2]. These timers can be adjusted from zero second up to 24 hours. By adjusting these 4 parameters ([VT-], [VT+], [T1], and [T2]) you can get a great system flexibility. A software that allows you to setup the parameters is provided free of charge. If necessary (for example the battery is not able to reach the [VT+] level) you can set up a TIME-OUT timer that shutdown the system. In this case a manual reset, by removing the DC supply, is necessary to restart the module.

VDC Battery Monitoring Relay Wiring Diagram

The connections of the Be48 module are simple to understand and easy to make. The supply requires a 12Vdc-30Vdc voltage. You may use the battery of your power generator. It could be 12V or 24V but, in this case of 12V battery you may experience with a voltage drop during engine crank. The output is 'STATIC' via an internal switching 12V-100mA power supply. You can connect a small automotive relay or you can directly connect the output to the REMOTE START input of your engine AUTO START module. Output is short-circuit proof. The RS232-USB port is used to configure the settings of the module. You are required to use the USB cable included in the box. Use USB-A for the computer and USB-B mini for the Be48. To allow Battery Voltage measurement, you are required to connect the terminals 40-400 for high voltage battery or 0-60 for low voltage battery. The module can support reverse polarity for unlimited time. We always recommend to protect the wires using a 1-AMP fuse 5X20mm size for low volatge and a 4 Amp 10x38mm size for high voltage battery. The BE48 allows floating or "grounded" batteries. The RS485 serial interface is available only on request, you should not connect the 4-poles plug.

Battery Monitoring Relay Mechanical Details

The Be48 Battery Monitoring Relay is intended for DIN rail mount inside a control panel. We recommend that you choose the vertical position. The Be48 works in a wide operating temperature range of about -25 up to 70 degrees Celsius. Total weight is about 240 gr. Connectors for supply and voltage monitoring are standard, removable 5mm pitch, male-female plugs. The RS232 connector features an embedded USB-B MINI female FTDI adapter. A cable, 1m long, with USB-A and USB-B MINI is included in the box. The 4 poles male-female plug, pitch 3,81, is used for the optional RS485 serial interface (only available on request).

ELECTRICAL SPECIFICATION

POWER SUPPLY PLUS: 08VDC up to 30VDC

POWER SUPPLY MINUS (TO GND): +/- 24VDC

POWER SUPPLY CURRENT (STAND-BY) 30mA

POWER SUPPLY CURRENT (OUTPUT ON) 30mA MAX.

OUTPUT VOLTAGE (ON STATE): 12VDC 

OUTPUT CURRENT (ON STATE): 100mADC

OUTPUT VOLTAGE (OFF STATE): 0,5VDCMAX 

OUTPUT CURRENT (OFF STATE): -5 mADC

POWER SUPPLY GROUNDING: MANDATORY

BATTERY (MONITORING) PLUS: 0VDC + 400VDC MAX

BATTERY (MONITORING) MINUS: 0VDC 

BATTERY (MONITORING) TO GND:+/- 400VDC MAX

MANDATORY FUSE PROTECTION: 4A 10X38 FAST

INPUT IMPEDANCE (0-400V INPUT): 500K HOM

INPUT IMPEDANCE (0-60V INPUT): 100K HOM

RS232-USB PORT: NON-ISOLATED

COMMUNICATION BAUD RATE: 19200 BPS

BATTERY (MONITORING) GROUNDING: NOT MANDATORY

Configuring the Battery Voltage Monitoring Relay

HOW TO ADJUST THRESHOLDS AND TIMERS USING A COMPUTER

We provide a free of charge software that allows you setting up the module. Make sure that the SUPPLY MINUS of the Be48 is at the same potential of your computer. In other words, the best safety condition is obtained when the DC supply is connected to the battery minus of the power generator (battery minus must be grounded). Before running the software you are required to connect your  computer to the Be48 MODULE (via USB cable) and turn on the DC supply (12Vdc-30Vdc). The USB cable features a USB-A plug for your computer and a USB-B mini for the BE48 module.  You can set Voltage thresholds and various timings. When the precision is mandatory, you can calibrate down to zero the measurement error. This will compensate ground loop errors, noise and miscellaneous error sources. The software provides accurate reading of the power supply as well.  Normally, the power supply voltage is connected to the battery of the power generator. Battery System is usually a backup battery pack of a solar system for example. This could be in the range 0 up to 400V isolated or non-isolated to ground. You can connect the computer at anytime without affecting the system only if the MINUS VDC supply terminal is grounded.  When you set up the system you can test the output by using the ON-SCREEN test button.

VOLTAGE MONITORING RELAY OVERVIEW

After wiring the Be48 MODULE, you are required to connect the USB cable to your computer. Run the BE48 DC VOLTAGE MONITORING software. The computer will automatically search for the serial connection port. A green message 'CONNECTED' will indicate the communication between BE48 and your computer. The software provides measurements of the power supply voltage and battery system voltage.

VOLTAGE MONITORING RELAY SETTINGS

The basic available commands are SAVE (to store a parameter), DEFAULT (to use factory settings) and RELAOD (it cancels a modification and restore the previous setting). If you modify a parameter, a yellow backgroud will warn you. Once stored in the memory the yellow background wll disappear. Low Voltage Start is the voltage level of the battery that triggers the timer T1 (once T1 expires, the engine starts). High Voltage Stop is the voltage level of the battery that triggers the timer T2 (Once T2 expires, the engine will stop).

VOLTAGE MONITORING RELAY TIMIMG SETTINGS

START & STOP delay timers are used to provide flexibility to your application. You can use these two timer to avoid false start and stop commands. As a matter of fact the voltage comparator itself has no response delay. It works immediately. This may cause a system instability. You can put, if you wish, the timers to zero at anytime. This can be usefull in particualr applications in which you need a fast respomse of the voltage comapator or you need to carry out tests of the system without waiting for delays.

VOLTAGE MONITORING RELAY SHUTDOWN SETTING

This additional timer is extremely important when you want to add security to your system. If there is a failure on the charger, you will never be able to charge the battery. The generator will run for hours and hours without benefit in return. This timers limits the run time of the engine. One the BE48 triggers the alarm, you are required to remove the power supply for a few seconds to restart the module.

CALIBRATING THE MONITORING VOLTAGE RELAY

Factory precision of the measurements is about 2%. If this error is not accettable, we recommend that you carry out the calibration. This is really simple. You will put a precise measurement instrument on the battery and yu will take note of the measurement. Then, you will type on the screen the value. After pushing the button 'SAVE', the Be48 will calculate the correction factor. You will get in a few seconds the reading with approximately 'NO ERROR'. A good calibration will allow you a 0,1% accuracy. The calibration is stored in a NON VOLATILE memory.

VOLTAGE MONITORING LOG HISTORY

If you want to carry out really accurate testing of the system, the BE48 provides real time data logger. By analyzing the TIME STAMP you can find out if the sysem works as you expect.