Signametrics
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Channel relays, Configuration relays and Treeing relays are cleaned by this function. The test connector must be in
place in order to perform this operation. This function returns an error if the test connector is abscent. Cleaning
takes about 13 seconds.
4.2.10 Integrity Test
The Integrity test is a quick verification tool. The
SCANTestChanIntegrity()
function tests the integrity of the
specified channel relay, by verifying that the currently set actuation and release times are adequate. The release time
is assumed to be 1/2 of the actuation time. This procedure closes the relay, waits for a time equal to the actuation
time, then it tests for contact closure on both contacts. Next it opens the channel relay, waits for a period equal to
the release time, and verifies that the relay is open.
This test does not include bounce test. Use the
SCANTestChannelRelay()
and
CANTestConfigRelay()
functions
for a more comprehensive test. This test does not verify bounce
The test connector must be present in order to carry this operation. If the test connector is not present, this function
returns an error. Cleaning takes about 13 seconds.
4.2.11 Self Tests
These comprehensive tests consist of the Channel Relays test and the Configuration Relays test. They provide the
confidence of knowing that the Scanner is in good repair, and can continue in its operation. The two tests are
applied to a single channel: configuration or tree relay. These tests diagnose excessive bounce, open failure, and
short failure. If no failure is detected, these functions measure and return the actuation time for the selected relay.
The actuation time measured includes closure time plus bounce time. The results of these tests can be used to fine
tune the scanner for maximum switching time performance by either, setting the highest relay’s actuation time
(using the
SCANSetActuationTime()
function), or setting individual actuation time prior to selecting each channel.
The value of the measured actuation time is an indicative of the condition of the selected relay. A value higher than
that specified for the Scanner is an indication of relay deterioration, which may require relay replacement. These
tests require the test connector.
Channel Relays Test
Each Channel may be tested using the
SCANTestChannelRelay()
function. The Channel parameter can be a value
between 1 and 32. If no failure is detected, this function returns the Actuation time for the relay.
Configuration Relays Test
Each Configuration and Tree relay may be tested using the
SCANTestConfigRelay()
function. Configuration relay
can be AtoA, BtoA, BtoB/Ch33, CtoA, CtoC/Ch34, DtoC, or DtoD/Ch35. See the
ScanUser.H
file for definitions of
these relays. If no failure is detected, this function returns the Actuation time for the relay.
4.2.12 Setting Actuation Time Parameter
The Actuation time includes the time a relay closes and settles. It is made up of both, the Operate time and Bounce
time. Each relay has different actuation time, and therefore it is a good idea to keep the default 10ms Actuation time.
Alternatively, one can measure all relays, and set the Actuation time to the slowest relay of the Scanner. Actuation
time may vary with age, and could be an indication of fatigue of the relay. Configuration and Tree relays may be
measured using the
SCANTestConfigRelay()
function and the channel relays using the
SCANTestChannelRelay()
function. Set the Actuation time using
SCANSetActuationTime ()
and read it with
the
SCANGetActuationTime()
function. The SMX4030 family of Scanners have a special active Release (drop-out
time) circuit, which forces all relays to release much faster than operate. For this reason, the Actuation time also
includes the release of a currently closed channel, in a break before make multiplexing. In configurations such as
the
TwoWire, FourWire, SixWire, TwoGroups,
and
FourGroups
, the Actuation time includes both the release and
operate processes. When enabled, the trigger output signal corresponds to the Actuation time. The trigger polarity
may be set positive or negative to provide means for triggering external devices when the switching is settled.
Further, the Actuation time maybe set to a value higher than necessary for relay actuation to provide delayed trigger.
Actuation time may be set to a value between 1ms to 850ms.
4.2.13 Setting Step Time Parameter
This parameter is the Auto Scan period, or step time. It maybe set to a value between 1ms to 850ms. On power up, it
defaults to 100ms. It is the channel to channel scan time in Auto Scan. Use
SCANSetStepTime()
to set it and