Thermo Fisher Scientific Alpha pH 1000 - Manual (Page 6)

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1 INTRODUCTION
1.1 Description of Unit
Thank you for purchasing the ¼ DIN Alpha pH1000 pH/ORP process controller/transmitter.
This unit is used for measuring either pH or ORP parameter one at a time, and the
operational mode is switchable from the menu. You can use this unit to measure pH or ORP
with limit control. This controller has many user-friendly and safety features which include:
•
Menu-driven program that simplifies set-up
•
Built-in non-volatile memory backup to ensure that calibration and other information
are not erased if power supply fails
•
Press-button two-point calibration and electrode offset adjustment from the
keypad
•
Automatic temperature compensation (ATC)
•
Manual temperature compensation setting without the ATC probe, with independent
setting for calibration and process temperature
•
0 to 2000 second time delay adjustment on all relays – minimise false alarms
• Separately
adjustable high and low set point hysteresis (dead bands) prevent
chattering of relays around the set points
•
Asymmetrical/symmetrical input for pH/ORP operation
•
Three control modes: limit, proportional pulse length or proportional pulse frequency
•
Large dual display LCD for easy reading with clear multiple annunciators, alarm
status, operational and error messages
•
Two switching contacts as set-point triggering relays
•
A third relay that can be be set up to perform either Alarm or Wash function
•
When set to work as Alarm relay, alerts you when readings exceed set-point limits after
a set time buffer, and if the Pt100/Pt1000 wires are broken or disconnected during the
ATC function
•
Programmable duration and frequency in the Wash mode
•
Hold function freezes output current (0/4…20mA) and releases control relays
•
LED indicators signal control activities to monitor controller status from a distance
•
Protection against electromagnetic interference – galvanically isolated 0/4…20mA
output provides safety for datalogging and control purposes
•
Choice of 7 buffers from USA or NIST standards
1.2 Applications
Use this controller in panel mounted enclosures for applications such as water treatment and
monitoring, galvanic-decontamination, chemical processing food processing, clean or waste
water control and neutralisation process.