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SECTION 8 – INPUTS AND OUTPUTS
Optically Coupled Inputs
All inputs to the 9000TS System are optically coupled to increase the tolerance of the
system to noise interference and to allow operation from AC or DC voltage sources.
Digital Inputs
P925TS-I Input Cards are designed to operate from either normally open or normally
closed volt free contacts with a fused +24VDC being supplied by the 9000TS System
for use as a signal supply voltage.
As an alternative the customer can use 24VDC powered Inputs which connect directly
to the associated Input card. If powered inputs are required the OV reference of the
customers supply should be connected to the OVC IN terminal on the rear of each
chassis as this links the common return path of all of the optically coupled inputs.
As an option higher voltage powered inputs can be used, typ125VDC, and each
channel is equipped with a 3 pin header and 2 way shorting bar which allows the user
to set the input to match the required signal supply voltage level.
For example: The standard input card allows selection of 24VAC/DC OR 125VAC/DC
and an
optional card
is available for systems requiring 48VAC/DC OR 250VAC/DC
As field contacts are often located a long way from the associated logic it is
recommended that input cables be run separately from circuits carrying heavy currents
or high voltages to minimise the effects of induced voltages. All inputs are provided
with transient filters so that low voltage interference is ignored
.
Lock In
Each channel can be software configured to capture fleeting alarms or to allow them to
automatically return to the off state as soon as the contact returns to normal.
Lamp/LED Outputs
P925TS-O Output Cards, located in the adjacent slot to P925TS-I Input Cards, allow
connection to conventional remote mounting lamp / LED displays. Each of the 16
outputs is short circuit protected and capable of driving 160mA @24VDC.
Repeat Relay Option
P925TS-R Repeat Relay Cards provide 16-volt free contact outputs. Each output can
be set to normally open or normally closed using 3 way header pins and 2 way
shorting bars on a per channel basis as required. The repeat relay feature is typically
used to provide an isolated input to 3
rd
party Scada packages.
Dual Horn Relay
Two of the common relays RL1 and RL2 are factory set as horn relays and these can
be used to connect to remote audible devices. The remote audibles are often referred
to as priority and non-urgent and provide the operator with distinct tones that help
determine the speed of response required.