Signal Inputs Of Remote I/O And Memory Access - Extech Instruments 7470 Operation Manual

detecting that the item under test passed all tests. The connection is opened when
the next test is initiated or the reset function is activated.
FAIL – The relay contact closes the connection between pin (3) and pin (4) after
detecting that the item under test failed. The connection will open when the next test
is initiated or the reset function activated.
RESET OUT – The relay contact closes the connection between pin (7) and pin (8)
while the reset function is activated. This is only a continuous closure dependent on
the length of time the reset button is held in an active state.

8.2. Signal Inputs of Remote I/O and Memory Access

The High Withstand Voltage Tester remote connector enables remote operation of the
TEST, RESET, and REMOTE INTERLOCK functions, and allows the operator to select
Memory 1, Memory 2, and Memory 3.
When the PLC Remote mode is on, the High Withstand Voltage Tester will respond to
simple switch or relay contacts closures. A normally open momentary switch can be
wired across pins 3 and 5 to allow remote operation of the TEST function. A minimum
pulse width or contact closure of 20mS is required to guarantee a test start. A
normally open momentary switch can be wired across pins 2 and 5 to allow remote
operation of the RESET function. A minimum pulse width or contact closure of 50mS
is required to guarantee that a running test will abort. When the PLC remote function
is (ON) the TEST switch on the front panel will be disabled to prevent a test from being
activated through this switch. For safety, the front panel RESET switch remains active
even when a remote reset switch is connected so that high voltage can be shut down
from either location.
The High Withstand Voltage Tester also allow access to three MEMORY PROGRAMS
through the remote control connector. This gives the user the capability to quickly
change parameters and initiate a test remotely. The built in memory programs of the
instrument are used to accomplish this. Three internal memory programs can be
accessed, by connecting terminals 7, 8, and 9 in different combinations. The memory
select lines should be set simultaneously and remain set for a minimum of 20ms to
guarantee that the correct memory will be selected. However, the memory select bits
may be set in sequential manner, provided that the time delay between each bit is less
than 4ms. When the desired bit pattern has been established it should remain set for
a minimum of 20ms to guarantee that the correct memory will be selected. It may be
necessary to "OR" the momentary switches (relay contacts) to prevent incorrect
program selection due to timing errors.
MEMORY
54
ACTIVATING MEMORY PROGRAM FUNCTIONS THROUGH
THE REMOTE CONNECTOR, SELECTS THE PROGRAM AND
STARTS THE TEST WHICH IS PREPROGRAMMED INTO THAT
DO NOT CONNECT VOLTAGE OR CURRENT TO THE SIGNAL
INPUTS, THIS COULD RESULT IN DAMAGE TO THE
CONTROL CIRCUITRY.