OSRAM QUICKTRONIC INTELLIGENT DIM CFL - Manual (Page 46)

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3.5.1.2 Control via analog output
The external control with an analog output 0…10 V (e.g. PC card)
is basically possible. This control module must be capable of taking
the current supplied by the ECG in the control line and of reducing
the control voltage to at least 1 V. For that reason, however, the ana-
log output must fulfill two requirements: It must be potential-free and
may not therefore be connected galvanically with touchable parts or
circuits that are subject to SELV requirements (test voltage 2500 V,
the test voltage to grounded parts is 1500 V). The analog output can
operate as a current sink because it must take the control current of
the OSRAM DIM ECG. Mostly, it is not known whether and how much
current an analog output can take but assistance can always be pro-
vided by an interface circuit.
3.5.1.3 Interface circuit
In the case of up to three OSRAM DIM ECGs, it is recommended to
connect the control inputs of the ECG directly with the analog output
(e.g. PC card) and, in the case of four and more OSRAM DIM ECGs,
to interconnect a signal amplifier. Then start up the system, set the
control voltage to 0 V and check with a multimeter directly at the ana-
log output. If the measured value is less than 1 V, the situation is okay
and the system can be started. If the control voltage here is greater
than 1 V, the analog output cannot take enough current and an addi-
tional current sink is required in the form of a parallel switched resistor
R. The required value is determined as follows: At a default control
voltage of 0 V, a potentiometer (approx. 5 k
Ω
linear) is also set on the
analog output and a 1 V control voltage set with it. Disconnect the po-
tentiometer and measure the resistance value (must be greater than
680
Ω
), provide and connect corresponding fixed resistor (construc-
tion form 0207, power rating 0.25 W, possibly next smaller resistance
value).
Analog output,
e.g. PC
+
–
+
–
Dimm-ECG
+
–
+
–
In
DIM SA
signal
amplifier
Out
if necessary
R
Figure 27: Control via PC