Hall Research HR-1P - Manual (Page 9)

9
Model HR-1P Projector Controller
SPECIAL CONNECTION INFORMATION
:
• By default the HR-1P is configured to detect a
CONTACT or a NON-ISOLATED VOLTAGE. By
special request at the time of the order, the unit can
be configured to detect an OPTICALLY ISOLATED
VOLTAGE.
• Both the CONTACT/NON-ISOLATED and
OPTICALLY ISOLATED configurations use the EXT
CTL jack for detection of the signal.
• For Contact/Non-Isolated Voltage
configurations of the unit, ALWAYS ensure that if
you supply a voltage to the EXT-CTL jack, it is applied
as CENTER POSITIVE in the range of 3-24 vDC. The
device will not sense 0 volts by unplugging the EXT
CTL jack. The sensing circuit is normally ‘pulled’ high.
This means that in order to detect the ‘No-Voltage
applied’ condition, your circuit must represent a low
resistance.
• For OPTICALLY ISOLATED configurations,
ALWAYS ensure that the voltage is applied as a
CENTER POSITIVE in the range of 3-9 vDC. This
voltage should be isolated from the units Supply
Voltage.
• Failure to observe these warnings may result in
damage to the unit and void your warranty