MKS MKSINST IE1000A, Инструкция по эксплуатации

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Chapter Three: Operation Analog 15-pin Interface Operation
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Chapter Three: Operation
Analog 15-pin Interface Operation
The IE500A / IE1000A High Flow Rate Mass Flow Controller analog I/O interface is available in a standard
15-pin DSUB male connector through which both power and signal I/O are routed.
Analog I/O Interface Cable Requirements
As of January 1, 1996, all products shipped to the European Community must comply with the EMC Directive
89/336/EEC, which covers radio frequency emissions and immunity tests. MKS products that meet these
requirements are identified by application of the CE Mark.
This MKS product meets CE Mark requirements, per EMC Directive 2004/336/EEC. To ensure compliance
when installed, an overall metal braided shielded cable, properly grounded at both ends, is required during
use. MKS offers a variety of interface cables listed in the tables which follow.
Table 7: MKS Interface Cables
Power Supply End
MFC End 15-
Pin Type “D”
Flying Leads
Analog 15-pin DSUB CB147-1
CB259-5 CB259-6
Note An overall metal braided, shielded cable, properly grounded at both ends, is required to meet CE
Mark specifications.
Note
To order an overall metal, braided, shielded cable, add an “S” after the cable type designation.
For example, to order a standard connection cable to connect the MFC to a power supply with a
15-pin DSUB connector, use part number CB259-5; for an overall metal braided, shielded cable
use part number CB259S-5.
Analog I/O User Supplied Shielded Cable Requirements
MKS offers a full line of cables for most MKS equipment. Should you choose to manufacture your own
cables, follow the guidelines listed below:
1. The cable must have an overall metal braided shield, covering all wires. Neither aluminum foil nor
spiral shielding will be as effective; using either may nullify regulatory compliance.
2. The connectors must have a metal case with direct contact to the cable shield on the whole
circumference of the cable. The inductance of a flying lead or wire from the shield to the connector
will seriously degrade the shields effectiveness. Ground the shield to the connector before its internal
wires exit.
3. With very few exceptions, the connector(s) must make good contact to the device’s case (ground).
Good contact is less than 0.01 ohms and the ground should surround all wires. Contact to ground at
just one point may not suffice.
4. For shielded cables with flying leads at one end; it is important to ground the shield at the end before
the wires exit. Make the ground connection with absolute minimum length. (A ¼ inch piece of #22
wire may be undesirably long since it has approximately 5 nH of inductance, equivalent to 31 ohms at
1000 MHz). After picking up the braid ground, keep wires and braid flat against the case.