Innotech Genesis V4 System - Manual (Page 70)

Installation Instructions for Innotech Genesis Systems
Edition 011100 4-15
Procedures for performing voltage checks are:
CAUTION
ENSURE THAT NO AC VOLTAGE IS PRESENT ON EITHER
TERMINAL. AV VOLTAGEAT THE INPUT TERMINALS CAN
CAUSE DAMAGE TO THE UNIT. ALSO, THE UNIT WILL NOT
OPERATE PROPERLY IF THE ANALOGUE INPUT SIGNAL
POLARITY IS INCORRECT.
a. Ensure all AISCs have been removed and no power is applied to the Genesis unit.
b. Connect a digital voltmeter to the input terminals; set the voltmeter to indicate Vac.
Ensure there is no AC voltage present on either terminal. If AC voltage is
measured, check the analogue input wiring for faults/errors
c. Set the digital voltmeter to indicate Vdc. Set the range for the expected voltage
value shown in Table 4-3.
d. Connect the voltmeter across the analogue input terminals observing polarity. If
necessary, reduce the voltmeter range to obtain an accurate reading.
e. Ensure the measured voltage is within the expected range and of the correct polarity.
If not, check the analogue input wiring for faults/errors
f. Repeat Steps b. through e. for the remaining inputs associated with the AISC models
noted above.
4-1.2.4.2. Current Checks. This paragraph contains procedures for checking
analogue inputs associated with AISC Models I05, I20, P20, TD1 and TD2.
CAUTION
PROCEDURES IN THIS PARAGRAPH REQUIRE CONNECTING
A 500 OHM RESISTOR ACROSS THE ANALOGUE INPUT
TERMINALS AND MEASURING THE RESULTANT VOLTAGE.
ALTHOUGH 500 OHMS IS SUITABLE IN MOST CASES, SOME
APPLICATIONS MAY REQUIRE A HIGHER VALUE OF
RESISTANCE TO AVOID DAMAGE TO CIRCUITS. ALWAYS
ENSURE THAT A SUITABLE RESISTOR IS USED.
Analogue inputs associated with the I05, I20, TD1 and TD2 AISCs are checked by
measuring voltage across a resistance connected in series with the current source. A
500-Ohm resistance is normally suitable for this procedure. The matrix below lists the
expected voltages to be measured across a 500-Ohm resistance for the various values of
input current. For other resistor values use Ohm’s Law (E=IR) to determine the voltage.
AISC
INPUT VOLTAGE