AE Techron 7548, Operator'S Manual

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Information subject to change
97-7796264_09-04-2020
7548/7794/7796/7796HC OPERATOR’S MANUAL – SECTION 5
28
STEP 3: Determine if Default or Custom Compensation is Required.
If your load inductance is between 200 microHen -
ries and 1 milliHenry, and your load resistance
is less than 5 ohms, then you can likely use the
default compensation provided by the amplifier’s
factory-installed RC network. To select the factory-
default compensation, please see
STEP 4 below.
If your load inductance falls outside of the mid-
range, or if your load resistance is greater than
5 ohms, then you must calculate your required
compensation. If, after calculating your required
compensation, you determine that the default com-
pensation will be insufficient for your load, then
you will need to enable and install a custom RC
network. See
STEP 6 below.
AE Techron 7000 Series amplifiers can be enabled
with one of two compensation settings: default
RC network or custom RC network. The required
network can be selected via jumpers on the main
board. CC1 enables the default (factory-installed)
RC network, while CC2 allows installation of a cus-
tom RC network.
Figure 5.9 describes the default
RC circuit.
To select CC1, place jumper J5 in the UP posi -
tion; to select CC2, place jumper J5 in the DOWN
position. (For jumper location, see the
Advanced
Configuration section.)
IMPORTANT: If CC2 is selected, you must cal -
culate the compensation requirements for your
custom RC network and install the network on
your amplifier main board before operating the
amplifier in CC mode.
STEP 4: Enabling Your Compensation Setting.
STEP 5: (Optional) Verify Suitability of Default Compensation (CC1)
If desired, the following values of the components
contained in the default RC network can be used
with the formulas provided in
STEP 6 below to
verify the suitability of the default compensation for
your uses.
Pins Jumped: 1 and 2 (UP)
Compensation Resistor: R63 (68 Kohms)
Compensation Capacitor: C16 (0.047 µF)
Parallel Capacitor: C11 (47 pF)
STEP 6: Installing an RC Network for Custom Compensation
If the default RC network does not provide suit-
able compensation for your intended load, you
will need to install a custom RC network that is
matched to your load. This network will require two
components (a resistor (R) and a capacitor (C))
to be installed on the main board. To calculate the
approximate values required for each component,
use the following formulas.
COMPENSATION FORMULAS:
To find the value for the resistor (Rc) in the RC
network:
Rc = 20,000 x 3.14 x L x BW where:
Rc is compensation resistance in ohms.
L is load inductance in henries.
BW is bandwidth in hertz.
To find the value for the capacitor (Cc) in the
RC network:
Cc = L/ (R x Rc)
where:
Cc is compensation capacitance in farads.
L is load inductance in henries.
R is resistance of load in ohms.
Rc
is compensation resistance in ohms.