Contemporary Control Systems BASremote Installation Guide - Manual (Page 16)

TD040300-0II
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excursions will be ignored. It is still possible to detect the input signal
by only sensing the positive excursions.
When interfacing to a pulse device that has an opto-isolated open-collector
output, a pull-up resistor must be added to the device output. In Figure 13,
a 3-phase wattmeter has three opto-isolated open-collector outputs, each
requiring an external pull-up resistor. Since each of the opto-isolators
is rated for 60 VDC, install a 100 kΩ pull-up resistor between each
output and the +24 V loop supply. The common of the opto-isolators
connects to the common of the BAS Remote. Since each BAS Remote
input has a 100 kΩ input impedance, the resulting voltage divider sets
the off-state voltage to 12 V. Even though the BAS Remote input
range is 0–10 VDC, this will not harm it. Set the two thresholds to 2 V
and 3 V. The threshold points on digital signals are not critical.
Consult the pulse device manual for more guidance.
Analog Input
Either voltage in the range of 0–10 VDC or current in the range of 0–20
mA can be measured with an analog input. Transmitters that produce
an elevated ―zero‖ such as 2–10 VDC or 4–20 mA can be measured as
well. Using the web page, configure the input for either voltage or
current and select an appropriate range. Scaling the input is accomplished
by assigning the low and high points to engineering units. When set as
a voltage input, the input impedance is 100 kΩ and for a current input,
the impedance is 250 Ω.
With voltage measurement, connect the more positive voltage to point
A and the less positive to BAS Remote common as shown in Figure 14.
On three-wire devices such as damper actuators, the output signal is
referenced to the damper’s power supply common. That common must
be at the same reference as the BAS Remote common. Notice the
connections in the diagram. In this situation it is only necessary to
attach the transmitter output to point A on the BAS Remote input.
When measuring current, remember the BAS Remote sinks current to
ground. A 250 Ω impedance is effectively applied between points A
and B on the input. To measure current, it must be driven into point A
with respect to point B. For two-wire current transmitters, the more
positive point on the transmitter attaches to the +24 V on the BAS
Remote loop supply or it can attached to an external loop supply as long