Using The Remote Start/Stop Cable; Connecting Agilent Products; Connecting Non-Agilent Products - Agilent Technologies 8860 Installation And First Startup

B Cabling Diagrams and Remote Start/Stop

Using the Remote Start/Stop Cable

Remote start/stop is used to synchronize two or more instruments. For example, you might
connect an integrator and the GC so that the
both of them. You can synchronize a maximum of ten instruments using Remote cables.

Connecting Agilent products

If connecting two Agilent products with Remote cables, the sending and receiving circuits will
be compatible—just plug in both ends of the cable.

Connecting non-Agilent products

If connecting to a non-Agilent product, the following paragraphs contain information you will
need to ensure compatibility.
APG Remote signal electrical specifications
The APG signals are a modified open collector type. The signal levels are generally TTL levels
(low voltage is logic zero, high voltage is logic one) but the open circuit voltage will be between
2.5 and 3.7 V. The typical voltage is 3 V. A voltage over 2.2 V will be interpreted as a high logic
state while a voltage below 0.4 V will be interpreted as a low logic state. These levels provide
some margin over the specifications of the devices used.
The pull-up resistance, connected to the open-circuit voltage, is in the range of about 1 kOhms
to 1.5 kOhms. For a logic-low state, for a single device on the bus, the minimum current you
must be able to sink is 3.3 mA. Since devices are connected in parallel, when you have multiple
devices this minimum current must be multiplied by the number of devices attached on the
bus. The maximum voltage for a low-input state is 0.4 V.
The bus is passively pulled high. Leakage current out of a port must be less than 0.2 mA to
keep the voltage from being pulled lower than 2.2 V. Higher leakage current may cause the
state to be interpreted as a low.
Over-voltage protection: APG Remote connections are clamped by a zener diode to 5.6 V.
Exceeding this voltage will damage the circuit (GC logic board).
APG Remote - Suggested drive circuits
A signal on the APG bus may be driven by another APG device or by one of the following
circuits:
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A relay, with one side connected to ground, when closed will set a logic-low state.
An NPN transistor, with the emitter connected to ground and the collector connected to the
signal line will set a logic-low state if proper base current is supplied.
An open-collector logic gate will perform this same function.
A low-side drive IC will also work, but Darlington-type drivers should be avoided as they will
not meet the low-side voltage requirement of less than 0.4 V
Start Stop
/ buttons on either instrument control
Installation and First Startup