Advantech PCL-725 User manual

PCL-725
Relay Actuator and Isolated D/I Card
USER'S MANUAL
COPYRIGHT NOTICE
This documentation is copyrighted 1989 by Advantech Co.,
Ltd. All rights are reserved. Advantech Co., Ltd. Reserves
the right to make improvements in the products described
in this manual at any time without notice.
No part of this manual may be reproduced, copied,
translated or transmitted in any form or by any means
without the prior written permission of Advantech Co., Ltd.
Information provided in this manual is intended to be
accurate and reliable. However, Advantech Co., Ltd.
assumes no responsibility for its use, nor for any
infringements of the rights of third parties which may result
from its use.
ACKNOWLEDGEMENTS
PC-LabCard is a trademark of Advantech Co., Ltd.
IBM and PC are trademarks of International Business
Machines Corporation.
MS-DOS is a trademark of Microsoft Corporation.
BASIC is a trademark of Dartmouth College.
Inter is a trademark of Intel Corporation.
Part No. 2003072500 4th Edition
Printed in Taiwan Sept. 1995

TABLE OF CONTENTS
CHAPTER 1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1. General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2. Features, Application and Specifications . . . . . . . . . . . . . . . . . . . 2
CHAPTER2. INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1. Initial Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2. Base Address Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
2.3. ConnectorPin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.4. Jumpers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.5. Installing The PCL-725 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
CHAPTER3. DIGITAL I/O PROGRAMMING . . . . . . . . . . . . . . . . . . 11
CHAPTER 4. CUSTOMIZE THE CURRENT LIMIT RESISTOR . . .13
CHAPTER5. RELAY OUTPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.1. Using the ContactProtection Nomograph . . . . . . . . . . . . . . . . ..16
AppendixA. I/Oport Address Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

CHAPTER 1. INTRODUCTION
1.1. General Description
The most common method of interfacing a microcomputer system, such as the
PC, is through the use of programmable digital input and output registers.
With digital output registers, the computer can write data into the registers,
treating the register as an I/O port. The output of these registers can then be
wired to an interface device, such as a relay. Thus, by writing data to an output
register, it would be possible to activate and deactivate a relay. The relay could,
in turn, control, for example, the power to a motor.
Digital input registers are similar but are used to sample the status of signals
attached to their inputs. For example, if a program wants to determine if a
switch is open or closed, the switch can be tied to the input of a digital input
register. A digital input register can be thought of as an I/O port that has wires
attached to individual bit locations. When read, the data results reflect the state
of the signals on the wires.
Designed with this idea in mind, the PCL-725 Relay Actuator & Isolated D/I
card is an IBM PC add-on card that offers you 8 relay actuators and 8 opto-
isolated digital inputs on a single board.
Typically, the 8 on-board relays can serve as ON/OFF control devices or small
power switches. The 8 opto-isolated D/I channels are ideal devices for
collecting digital inputs under noisy environment or floating potential. Also, the
8 isolated inputs provide the best method to prevent the ground loop problem.
For easy monitoring, each relay is equipped with one red LED to reflect its
ON/OFF status. Each input channel is jumper selectable to either isolated or
non-isolated input. Access to input and output channels is made possible
through a on-board 37-pin D type connector.

PCL-725 Introduction
1.2. Features, Application and Specifications
Features :
* 8 Relay actuator outputs.
* 8 Opto-isolated digital inputs.
* LED indicators to show activated relays.
* Jumper selectable isolated/non-isolated input signals.
* On-board relay driver circuits.
* On-board input signal conditioning circuits.
* Easy touse andprogram
Applications :
* Digital signal sensing.
* Switch contact status sensing.
* Limit switch monitoring.
* BCD interface.
* Industrial on/off control.
* Signal switching.
* Valve/solenoid control.
* External high power relay driving.
* Alarm activating.
* Annunciator control.
* Industrial automation.
* Laboratory automation.
* Useful with A/D's and D/A's.

PCL-725 Introduction
Specifications:
* Isolated Digital Input
Opto-isolator: 4N25
Input channels: 8
Input current: 60 MA max for isolated input. Input
buffered by voltage comparator
Input voltage: 5-24VDC
Input impedance: 560 Ohm/W
Threshold voltage: 1.5 VDC, adjustable by changing voltage
dividing resistors
Input mode: isolated or non-isolated
Withstanding voltage: 1500 VDC
* Non-isolated Digital Input
Logic level 0: 0-0.8 V
Logic level I: 2.0-5.25 V
" Relay Output
Relay Type: 4 SPDT (Form C)
4 SPST (Form A)
Contact rating: 120 V AC/DC, IA
Breakdown voltage: 1000 V AC/DC minimum
Operating time: 8 msec maximum (including Bounce)
Release time: 8 msec maximum
Insulation resistance: 100 MOhm minimum
Life expectancy: >10 million operations at full load
Power consumption: +12V, 33 mA for each relay, total
0.264A if ail relays are energized
+5V, less than 0.2A
Power supply: +12V from the PC bus

PCL-725 Introduction
* General
Dimensions : 5 3/4" x 3 3/4" (14.7 cm x 9.5 cm.)
Bus : IBM PC bus.
Slot : One 62-pin slot.
I/O port Address : Hex 200 - hex 3F8.

CHAPTER 2. INSTALLATION
2.1. Initial Inspection
Inside the shipping container, you should find this operating manual and the
PCL-725 card.
The PCL-725 was carefully inspected both mechanically and electrically before
shipment. It should be free of marks and scratches and in perfect electrical order
on receipt.
Remove the PCL-725 interface card from its protective packaging by grasping
the metal rear panel. Keep the anti-vibration package since it may be used to
return the card if it needs repair. The package may also be used if the card is
stored outside of the computer.
The board should be handled only by the edges. The integrated circuits on the
board can be damaged by static electric discharge.
2.2. Base Address Selection
Most of the peripheral devices and the interface adapters in the PC are
controlled and sensed using the digital input and output ports. These ports are
addressed using the I/O port address space of the 8088 or 80286 microcomputer.
The I/O port base address for the PCL-725 is selectable by an 8 position DIP
switch. Valid addresses are from hex 200 to hex 3FE. Refer to Figure 2.1 for the
location of the DIP switch (SW1).

PCL- 725 Installation
Figure 2.1 The PCL-725 Card
The required switch settings for various base addresses are illustrated as below :
Note : -ON = 0. OFF = 1
-"X" means "don't care"
-1..8 are switch positions
-A1..A8 correspond to address lines of the PC bus. A9 is
hard-wired to be 1.
-* means factory setting

PCL-725 Installation
-------------------------------------------------
I/O port switch position
address 1 2 3 4 5 6 7 8
(Hex) A8 A7 A6 A5 A4 A3 A2 Al
-------------------------------------------------
200-201 0 0 0 0 0 0 0 0
.
.
*2A8-2A9 0 1 0 1 0 1 0 0
.
.
2E8-2E9 0 1 1 1 0 1 0 0
2F8-2F9 0 1 1 1 1 1 0 0
3E8-3E9 1 1 1 1 0 1 0 0
3FE-3FF 1 1 1 1 1 1 1 1
2.3. Connector Pin Assignments
The PCL-725 card is equipped with a 37 pin D type connector accessible from
the rear plate. Please refer to Figure 2.1 for the location of the connector.
The following diagram below shows its pin assignments.
Legend:
DInL - digital input low, channeln
DInH - digital input high, channel n
GND -ground
NC n - normal close pin of relay n
NO n - normal open pin of relay n
COM n - common pin of relay n

PCL-725 Installation
NO 0 .1 20 . NO 3
COM 0 .2 21 . COM 3
NC 0 .3 22 . NC 3
NO 1 .4 23 . NO 4
COM 1 .5 24 . COM 4
NC 1 .6 25 . NO 5
NO 2 .7 26 . COM 6
COM 2 .8 27 . NO 6
NC 2 .9 28 . COM 6
NO 7 .10 29 . GND
COM 7 .11 30 . DI0L
DIOH .12 31 . DI1L
DI1H .13 32 . DI2L
DIZH .14 33 . DI3L
DI3H .15 34 . DI4L
DI4H .16 35 . DI5L
DI5H .17 36 . DI6L
DI6H .18 37 . DI7L
DI7H .19
2.4. Jumpers
There are two jumpers associated with each digital input channel for
configuring the channel as either isolated or non-isolated.
The following show the D/I channels and their corresponding jumpers :
D/I channel Jumpers
0JA0, JB0
1JA1, JB1
2JA2, JB2
3JA3, JB3
4JA4, JB4
5JA5, JB5
6JA6, JB6
7JA7, JB7
Examples are given here to illustrate how to configure the D/I channel. D/I
channel 1 is configured as isolated first, then non-isolated.

PCL-725 Installation
Isolated Non-isolated
-------- ------------
JA1 o o I JA1 o o I
o o N o o N
JB1 o o I JB1 o o I
o o N o o N
To configure channel 1 as isolated, the jumper plugs are installed on the upper
posts of JA1 and JB1. Otherwise, jumper plugs should be installed on the
lower posts to configure channel 1 as non-isolated.
2.5. Installing The PCL-725
POWER MUST ALWAYS BE SWITCHED OFF when removing or
inserting the PCL-725 card and connecting or disconnecting cables.
Use a screw driver to remove the cover mounting screws from the rear of the
system unit.
Slide the system unit's cover away from the rear and to the front. When the
cover will go no further, tilt it up, remove it from the base, and set it aside.
The PCL-725 is configured at the factory for the IBM PC, PC/XT, PC/AT and
all IBM PC compatibles. If you need further changes to the configuration
please refer to Chapter 2. Installation.
Use a screw driver to remove the screw that secures the expansion slot cover.
Save the screw for installation of the interface card.
The 37 pin connector should be pressed through the rear panel first, then press
the card carefully into the main board expansion slot.
Secure the PCL-725 with the 3/16" mounting screw, then attach an appropriate

PCL-725 Installation
cable to the connector.
Slide the system unit's cover back on. Align the system unit tabs with the
cover holes and reinstall the 1/4 mounting screws.

CHAPTER 3. DIGITAL I/O PROGRAMMING
On the PCL-725 card, 8 digital input channels and 8 relay output channels are
provided. Two I/O port addresses (started from BASE +0) are reserved for
accessing these channels.
The two addresses are allocated as :
BASE +0 D/O channel 0 - 7
BASE +1 D/I channel 0 - 7
A read operation on BASE+1 will read in the value (8 bits) of the 8
corresponding digital input channels.
To access these channels in BASIC, use the statement:
VALUE = INP(BASE+1)
A write operation on BASE +0 will set the desired status (1 =ON, 0 = OFF) on
the 8 corresponding relay output channels. To program these channels in
BASIC, use the following statement :
OUT BASE,XYZ
Where XYZ should be a number between 0 and 255. The status of the relay
outputs can be monitored by reading back the BASE+0 byte as shown below:
STATUS = INP(BASE)

CHAPTER 4. CUSTOMIZE THE CURRENT LIMIT RESISTOR
The default voltage input range of the PCL-725 is from 0V to 24V. To accept
higher voltage input, users can replace the current limit resistors, RAO through
RA7, for each channel.
It is easy to choose the proper current limit resistor. Since the 4N25 isolator has
a current rating of 60 mA, your input current can not exceed 60 mA. The
formula is shown as below:
Iin = Vin/Rlimit
where Iin:input current
Vin:input voltage
Rlimit:current limlit resistor
Note: It is suggested that the Iin is within 20 mA.
Additionally, you should consider the current limit resistor's maximum power
rating. The maximum power consumption should not exceed the power rating of
your resistor. The approximate formula is shown as below:
Pin=Vin*Iin
where Iin: input current
Vin: input voltage
Pin: input power
For example, if your maximum voltage input is 50V, and the current limit
resistor you choosed is 1K Ohm, then the maximum current input becomes
50mA. The power consumption of the current linmit resistor is approximately
2.5 Watts. In such situation, the power rating of your resistor should be more
than 2.5 Watts.

CHAPTER 5. RELAY OUTPUT
After power on, the initial relay output status of the PCL-725 is shown as
below:
Fig. 5-1
A write operation to I/O address, BASE+O, will change the output status of each
relay. For example, if Bit 0 of BASE+0 is set as "1" (logic high), relay 0, K0,
will switch from position "NORMAL CLOSE", NC0, to position "NORMAL
OPEN", NO0. This means that load2 will be de-energized, while loadl is
energized.
To summarize, the "COMMON" line connected to the "NORMAL CLOSED"
line, if the corresponding bit is set as 0 (power-on initial status). Otherwise, if
the corresponding bit is set as i, then the "COMMON" line will connect to the
"NORMAL OPEN" line.
Warning: External circuits connected to the PCL-725's relay output port
must be fused at 1A or less, and be rated at 120VA or less.
Voltage must not exceed +/- 120V peak.
For maximum relay contact life, and to prevent RFI if arcing occurs, contact
protection is required for inductive loads greater than 12 V, @64mA.
For more information, please refer to section 5.1.

PCL-725 Relay Output
5.1. Using the Contact Protection Nomograph
Loads which may cause relay contact arcing may also cause contact failure,
unless contact protection is provided. The nomograph, provided in Figure 5-3,
provides suitable guidelines for R-C network design for most loads. For PCL-
725, you should provide relay contact protection if the load to be switched is
greater than 12 V @ 65 mA. Figure 5-2 illustrates an example of a relay contact
protection network. For instance, if the load to be switched is 50 V @ 300 mA,
then R = 56 ohms and C = 0.009 uF (remember that, for PCL-725's relay output,
E = 120 V maximum).
The R-C network should be mounted as close to the relay contacts as possible.
NOTE: The nomograph indicates that for 70<E<100 V, R can be
+/- 50% of the nominal chart value.
Figure 5-2

PCL-725 Relay Output
Figure 5-3

Appendix A. I/O Port Address Map
I/O address Uses
range (Hex)
---------------------------------------------------------------
000-1FF Used by base system board
200 Not used
201 Game control
202-277 Not used
278-27F Second printer port
280-2F7 Not used
2F8-2FF COM2
300-377 Not used
378-37F Printer port
380-3AF Not used
3B0-3BF Monochrome and printer
3C0-3CF Not used
3D0-3DF Color & graphics
3E0-3EF Not used
3F0-3F7 5 1/4 inch diskette drive
3F8-3FF COM1