Dynamax AVRD 3.2 Manuale di installazione e funzionamento - Pagina 9

Sfoglia online o scarica il pdf Manuale di installazione e funzionamento per Controllore Dynamax AVRD 3.2. Dynamax AVRD 3.2 12. Voltage regulator

When the customer has 120 V AC or 220 V AC line power supplied nearby, the solar panel is

simply replaced by the battery charger and the battery size may be smaller than indicated. A

7 Ahr sealed lead acid battery has sufficient capacity for most applications. Model numbers

BA5A, and BA7A are the Dynamax products for 5A-hr and 7 A-hr batteries, respectively. The

4A-hr battery is recommended for measurement systems having four sensors or less.

Setting / Changing Voltage

Once the logger, AVRD and all cables are connected, the operation and set-up is quite easy,

simply follow the steps below.

The first time user should get a voltmeter and attach it to the Vin, and referencing

to ground. Make sure the voltage is greater than 10V if not charge the batteries

before proceeding.

If the voltage is greater than 10 VDC, turn the ON/OFF slide-switch to ON position.

Make sure Power LED is ON, if not check wiring to Vin terminal.

Attach voltmeter +ve to the Vout1 (V1), and referencing to ground. Then check

the sensor manual for the heater voltage. Turn on the AVRD adjustable knob

labeled Adj1. When you are ready, and turn the adjust knob clockwise to slowly

increase the voltage until the right setting is achieved. One turn is approximately

0.6 V increase (in clockwise direction) or increase (in counter clockwise direction).

Repeat the above step for setting the output voltage Vout2 (V2) from the AVRD.

Once the customer gets familiar with the logger operation, one may use the logger

to monitor the sensor supply, and make adjustments as needed. In this case the

logger acts as a voltmeter.

3.0 AVRD Applications

The purpose of the adjustable regulators from Dynamax is to have a stable, noise free

voltage excitation for sap flow sensors. Sap flow sensors offered by Dynamax are constant

heat energy balance sensors, and the TDP sap velocity sensors are steady state heat

dissipation sensors. In both methods one major benefit is the ease of supplying a constant

voltage to the heater elements. The devices that are responsible for providing a steady

regulated supply of voltage are the AVRD series of regulators.

In both methods of measuring sap flow differential temperature readings within the sensors

are functions of the heat flux or the dissipation of heat. In general, an accurate heat

flux measurement depends on the steady application of power to the heater elements.

Otherwise, a fluctuation in the power will cause an arbitrary temperature change, and

therefore a misrepresentation in heat flux as a change in sap flow.

New AVRD is a general-purpose adjustable voltage regulator for supplying excitation voltage to

a variety of sensors and DC powered systems. High current and high efficiency of this regulator

makes it extremely versatile for field applications where power consumption is critical. The following

table shows application and number of AVRD's configured with several Dynamax systems / kits.