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Patient Cable, ECG Cable, Disposable Probe
Advanced Medical Cables for Patient Monitoring
We engineer and manufacture instrument cables for the test and measurement industry. In addition to OEM instruments cables, we provide industrial automation and process control cables. In
this context, one of our specialties is GPIB cable (General Purpose Interface Bus) or IEEE 488 cable design and manufacturing.
Please see below some of the key types of instrument cables we offer:
Instrument Cables - GPIB tutorial
The GPIB / IEEE 488 interface bus, also known as the General Purpose Interface Bus "GPIB," is well established in the
electronics industry. It represents a robust means of providing control of remote test and measurement instruments via high
quality instruments cables. Although the GPIB cable interface has been in widespread use since the early 1970s, the use of the GPIB interface is finding new vitality in view of its convenience and availability. The GPIB cable and GPIB connectors are in widespread use and are available from many stockists and suppliers.
The GPIB interface is an 8 bit parallel interface system which incorporates:
The GPIB cable consists of 24 lines, with the remaining lines occupied by ground wires. The maximum data transfer rate is determined by a number of factors, but is about 1Mb/s.
GPIB Interface Connectors
The connector used for the IEEE 488 bus is standardized as a 24-way Amphenol 57 series type. This provides an ideal physical interface for the standard. The IEEE 488 or GPIB connector is very similar in format to those that were used for parallel printer
ports on PCs. This makes the GPIB cable a sufficiently rugged connection for use in a variety of test equipment and test and measurement environments where unprotected connectors may not survive well.
An additional advantage of the GPIB connector is that it has a screw-lock. In this way, once the connectors have been mated
the screw-lock can be used to secure the connectors together. In this way movements of the GPIB cables are unlikely to cause
any intermittent connections. With complicated electronics systems such as automatic test systems, intermittent signals in
instrument cables can cause significant problems which can be difficult to isolate and cure. By using a GPIB connector that has a screw-lock this problem can be overcome.
The basic female connector used on the GPIB cable applications follows the standard format for the Amphenol57 series,
however, the GPIB cable connector has some differences. The basic GPIB cable connector has a male to female capability. In
this several GPIB cables connectors can be "piggy-backed" on top of each other. This helps the physical setting up of the bus
and prevents complications with special connection boxes or star points, etc.
There are two different types of screwlockused on the GPIB cables. The metric threads are Black whereas English threads are
Silver. Unfortunately the two will not mate together. The most common type of screwlock is the black metric version.
GPIB Connector Pinout
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24-Pin GPIB Bus PinOut [IEEE488 Pinout]
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Pin #
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Signal Names
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Signal Description
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Pin #
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Signal Names
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Signal Description
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1
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DIO1
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Data Input/Output Bit 1
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13
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DIO5
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Data Input/Output Bit 5
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2
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DIO2
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Data Input/Output Bit 2
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14
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DIO6
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Data Input/Output Bit 6
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3
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DIO3
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Data Input/Output Bit 3
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15
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DIO7
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Data Input/Output Bit 7
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4
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DIO4
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Data Input/Output Bit 4
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16
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DIO8
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Data Input/Output Bit 8
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5
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EIO
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End-Or-Identify
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17
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REN
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Remote Enable
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6
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DAV
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Data Valid
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18
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Shield
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Ground (DAV)
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7
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NRFD
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Not Ready For Data
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19
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Shield
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Ground (NRFD)
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8
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NDAC
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Not Data Accepted
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20
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Shield
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Ground (NDAC)
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9
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IFC
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Interface Clear
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21
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Shield
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Ground (IFC)
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10
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SRQ
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Service Request
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22
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Shield
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Ground (SRQ)
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11
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ATN
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Attention
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23
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Shield
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Ground (ATN)
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12
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Shield
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Chassis Ground
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24
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Single GND
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Single Ground
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 GPIB cables
In practice the GPIB interface is very robust and easy to use for instrument cables. Ready-made GPIB cables are available even if they appear to be a little expensive. However these
GPIB cables are fully screened and have the correct lines as twisted pairs. This considerably reduces the susceptibility of the bus to data corruptions. The manufacturing of a full
specification GPIB cable can be somewhat costly in view of the complexity of the cable and having to ensure the integrity of the screening
IEEE-488 Cable Guidelines
Although there is a considerable degree of flexibility when setting up a GPIB interface, there are some restrictions on the way the GPIB instrument cables are set up. Up to fifteen instruments may be connected together with a maximum bus length not
exceeding 20 meters. There must also be no more than 2 meters between any two instruments. Devices on the GPIB can be connected in either a star or linear configuration.
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Multi-meter cables
