Delta CS24D - Manual (Page 11)

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4.1 Discrete I/O Specifications
CS24D Discrete I/O Specifications
Inputs Four (one group with common)
Input type 12-24VDC; sinking (sourcing drive)
Input Isolation 500VAC RMS optically isolated (see Section 4.3)
Input “High” range
(Teach and Hold) 7 to 29Vdc (polarity independent), 3mA maximu m
(Mode and Select) 8 to 29Vdc (polarity independent), 3mA maximu m
Input “Low” range
(Teach and Hold) 0 to 3.5VDC (polarity independent), <1mA
(Mode and Select) 0 to 2VDC (polarity independent), <0.1mA
Propagation delay
(Hold) 1.5ms maximu m to respond to Hold
(Teach, Mode and Select) 15 ms maximu m (de-bounced)
Outputs Four (one group with common)
Output type Solid State Relay (SSR)
Output Isolation 500VAC RMS optically isolated
Rated voltage 12-24V, ±30V maximu m (DC or peak AC)
Rated current ±50mA maximu m continuous, ±100mA maximu m peak
Propagation delay 1.5ms maximu m
Logic 0 (On) Low impedance (50 ohm, maximu m)
Logic 0 (Off) High Impedance (<1uA leakage current at 250V)
4.2 Hold Input
The Hold input provides a way to synchronize output data as follows. Once known good data is
present, turn on the Hold input to the CS24D. The outputs will stay in their current state until the Hold
input is removed. This prevents erroneous readings of the output condition. (Whenever
unsynchronized binary-coded data is read, there is always a possibility that the output may change
during the time the outputs are read, resulting in an incorrect reading).
If you wish to avoid using a PLC output to drive the Hold input on the CS24D, an alternate method of
ensuring correct data is to read twice and make sure the readings are identical.
When both Hold Input and Stretch Outputs are used, outputs will remain ON for the longer of the
Hold time or the Stretch time. (See section 7.1 for Stretch Outputs information).
4.3 Power Supply and Isolation
The CS24D requires a 12-24Vdc power source capable of supplying 50mA continuous and 500mA
peak startup current. In very critical applications, use a dedicated linear power supply that does not
supply other loads. A 250mA fast blow fuse must be used between the power supply and the sensor.
Inputs and outputs share a common pin but are fully isolated from the power input as well as the
CS24D internal circuitry and RS232 port. The power input is isolated from other pins. The RS232 port
is not isolated from the internal circuitry and is not intended to be connected during regular use of the
sensor.
Internal to the CS24D, a 1.00 Mohm resistor and small capacitor are connected between circuit
common and the enclosure in order to reduce noise picked up by the photodiode. For optimum noise
performance in some applications, it may be necessary to directly connect the CS24D internal common
to the CS24D enclosure. This can be accomplished by connecting Pin 3 of J1 (green wire) to shield.