Other controllersThe following procedure may be used to find out if the
EQ5 controller modification is likely to work with other controllers.
If the requirements above
are fullfilled, there is a good chance that a modification similar to the
one described for the EQ5-controller will work for your controller.
- You need a multimeter or a similar instrument capable
of measuring DC and AC voltage, current, and resistance.
- Measure the voltage from the power supply driving the controller.
The supply voltage should be maximum 30 V DC. The AC voltage should be
less than 30 % of the DC voltage. Identify the positive and negative
terminal in the connector.
- Disconnect the power cable and open the controller.
- Verify that the navigation buttons are ordinary switches:
- Each switch should have only two terminals in effective
use. Multiple solder pins may however be short
circuited form to form one effective terminal. This can be
checked by measuring the resistance between solder points.
- When the button is not pressed the resistance between the switch
terminals should be high (> 200 ohm). When the button is pressed the
resistance should be < 5 ohm.
- Each switches should have one of its terminals connected to the negative
supply voltage (usually ground). The resistance from the switch
to the negative syupply terminal should be < 5 ohm.
- Connect the power and the motor cables to the controller and turn it
- When a button is not pressed down, the DC
voltage across the switch should be > 3.5 V.
The negative side should of course be the side connected to the
negative supply. The AC voltage (rms) should not exceeds 30 %
of the DC voltage.
- When the button is pressed down the DC voltage across the switch
should be close to 0 V (or at least < 30 % of the DC voltage measured in
the last step).
- Put the multimeter in current mode and connect it between the
switch terminals. The DC current should be < 150 mA.
The AC current should be < 30 % ofthe DC current reading.
- Repeat step 7, 8, 9 with different motor speed settings, including at
least the highest and the lowest speed.
If you find that the navigation buttons consist
of switches, but the measured voltages and currents are not within the
ranges requested above, a possible solution may be to use relays coupled
that in parallel with the switches. The LN2003 circuit can then be used
to activate the relays.
Back to the EQ5 modification
Erlend Rønnekleiv, www.eronn.net
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