4
Using the Valve Unit and Valve-pump Controller
Servicing Your Valve System
Servicing Your Valve System
This section is intended only for use by Agilent Technologies service
personnel. It contains a description of the electronics and troubleshooting
procedures.
Logic levels of voltages are given as 0 for low level (approximately 0.7 V) and 1
for high level (approximately 4.8 V). To indicate negative true logic on signals,
a minus sign is appended to the signal description, for example Rdy(-) for the
ready signal.
Voltages are generally measured on the cables with all devices connected
because most of the outputs used are open collector without pull-up resistors.
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Agilent 8453 Dissolution Testing System Installing and Operating Manual