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BEW2000a Low Battery Throttle Inhibitor / Early Warning System
Table of Contents
Introduction Description Features Safety Threshold Mode 1 Mode 2
INTRODUCTION The BEW2000a is another innovative product from Micro Avionics and is the first-of-its-kind for the R/C Industry. It is a safety device that no R/C modeler should do without.
The BEW2000a can be used in virtually any type of radio controlled model, and is highly recommended for powered aircraft, helicopters, gliders, and speedboats.The condition of the model's battery pack has always been the concern of modelers whenever they operate their models. They know that the receiver battery pack on board their models will fast deteriorate whenever the output starts to fall below a certain voltage. When this happens, they would lose control of their model and its destruction will be inevitable. Worse still, their out-of-control model may even damage properties or seriously injure someone.
While dual-battery power systems may provide a backup power source, they still could not warn anyone of any low battery conditions. Furthermore, they also add unnecessary dead weight to your model, and require additional space for installation.
The BEW2000a allows you to use each battery pack in turn without the weight and space penalties. It is extremely easy to use and only requires a small screwdriver to set it up.
Many types of battery chargers and monitors are available in the market, all of which checks the battery condition when the model is not in operation. The most dangerous conditions occur only when the battery runs out of charge when the model is being operated: this is especially so for powered airplanes, helicopters, and power boats. No one is ever certain when this will happen.
The Micro Avionics BEW2000a is designed to eliminate this uncertainty, and add the element of safety to the operation of the model. Whenever the receiver battery starts to run out of charge, the BEW2000a will inhibit the throttle of the model's engine.
This inhibition will force the modeler to return the model to safe grounds and thus advert a potential disaster.
DESCRIPTION The Micro Avionics BEW2000a is a microprocessor-based device that is designed to monitor the battery supply voltage and to provide an early warning event whenever that voltage reaches a certain value.The BEW2000a can be used for both 4.8V and 6.0V battery systems. The user selects the type of battery pack in use from an integral switch array.
The user can also choose to operate the BEW2000a in one of 2 pre-programmed safety thresholds, which are 5% or 10% below optimum charge. These thresholds are also selected from the integral switch array.
There are 2 Modes of operation to choose from: Mode 1 and Mode 2.
In Mode 1, the BEW2000a will force the servo to a preset value, while in Mode 2, the BEW2000a will allow the servo to operate from 0% to a maximum of 50% travel. The maximum servo travel in Mode 2 can also be preset by the user. The preset values for the servo in either Modes, are adjusted via an integral potentiometer.
The BEW2000a also comes with a servo-reversal switch to drive the servo correctly without upsetting the transmitter setup of the model.
Connections to the receiver and the servo are via pre-harnessed 3-pole female and 3-pole male connectors respectively.
The compact size of the BEW2000a, which is about the size of a standard servo, makes is very easy to install in most models.
FEATURES- Microprocessor based design with low power electronics
- Powered from the receiver battery pack
- Constantly monitors the receiver battery voltage when in operation
- Simple to use: connects between the throttle servo and receiver
- Can be used in 4.8V or 6.0V battery systems (user selectable)
- 2 Safety Thresholds to choose from: 5% and 10% below full charge (user selectable)
- 2 Modes of Operation to choose from (user selectable)
- Adjustable servo preset position (Mode 1)
- Adjustable maximum servo travel (Mode 2)
- Connects to receiver via a pre-harnessed 3-pole female connector
- Connects to servo via a pre-harnessed 3-pole male connector
- Servo Reversal (user selectable)
SAFETY THRESHOLD There are 2 Safety Thresholds to choose from: 5% and 10% below the full charge voltage.The full charge voltage is dependent upon the type of battery system in use.For a 4.8V battery system, the Safety Thresholds are as follows:
5% Safety Threshold is at 4.56V
10% Safety Threshold is at 4.32V (not recommended for 4.8V battery systems)
For a 6.0V battery system, the Safety Thresholds are as follows:
5% Safety Threshold is at 5.70V
10% Safety Threshold is at 5.40V
MODE 1 In Mode 1, the BEW2000a will drive the throttle servo to a preset value whenever the battery supply voltage falls to the selected safety threshold.The preset value of the servo should preferably be set to the IDLE position of the model's engine. When activated, the BEW2000a will drive the throttle servo to the preset value and ignore the throttle commands from the Transmitter. This will create a condition that is similar to an engine flame-out.
Mode 1 is highly recommended for powered sport airplanes, especially those which are controlled from 4-Channel R/C sets.
When in the air, the flame-out condition will force the pilot to land the model before total control is lost due to a flat battery. This would be similar to a dead-stick landing. When on the ground, the idling engine will prevent the airplane from taking off.
However, for those who build and fly scale R/C airplanes, the idea of a flame-out condition may not be that appealing, eventhough the dangers of a flat battery is still very real.
In such cases, the BEW2000a can be used to optionally control a visual feature on the model as an early warning event. For example, in Mode 1, the modeler can use the BEW2000a to lower the landing gear, or open a sliding canopy when the battery supply is running low.
When these features on the model are activated without any commands from the transmitter, it would signal the pilot that the battery supply has reached the safety threshold. This is what we call an early warning event.
For gliders, thermal soarers and slope soarers, the BEW2000a can be used to extend a visual indicator to signal the pilot that the battery is getting low. These visual indicators can be in the form of a retractable mast or paper streamer.
MODE 2 In Mode 2, the BEW2000a will restrict the throttle servo to operate from IDLE to a maximum of half-setting only (0% to 50%), when the supply voltage falls to the selected safety threshold.The maximum setting of the throttle can be preset from anywhere between IDLE and 1/2 THROTTLE. This will allow the user to set the maximum throttle setting to suit the engine size.
When activated, the BEW2000a will allow the model's engine to be controlled from anywhere between IDLE and the preset value. When the throttle command from the transmitter exceeds the preset value, the BEW2000a will ignore that command and keep the throttle at the preset value.
When the throttle command is below the preset value, the BEW2000a will follow the transmitter stick setting.
Mode 2 is highly recommended for scale aircraft, helicopters and power boats. When the engine's power is suddenly limited to the preset value, it is an early warning sign to indicate that the receiver battery is about to go flat.
By restricting the power of the engine, the BEW2000a prevents the model from being operated to full capabilities. However, it still allows enough power to operate the model safely and bring it back to ground before everything fails.
TECHNICAL SPECIFICATIONS
Type Low Battery Throttle Inhibitor / Early Warning System Model BEW2000a Battery System
4.8V or 6.0V system
Selected by miniature array switchSafety Threshold
5% or 10% below Full Battery Voltage
Selected by miniature array switchOperational Modes
2 MODES
Selected by miniature array switchConnection to Servo Pre-harnessed 3-way Male Header Connection to Receiver Pre-harnessed 3-way Female Connector Operating Voltage 4.8Vdc to 6.0Vdc. Powered from Receiver Battery Pack Current Consumption Less than 20mA dc typical, not including servo load Dimensions (W x D x H)
46mm x 32mm x 16mm
1 3/4" x 1 1/4" x 5/8"
