Hach EC1000, Инструкция по эксплуатации

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SECTION 1 GENERAL INFORMATION
1.1 Instrument Description
The EC1000 Process pH/ORP Monitoring System consists of the Series EC1000
Controller, a Hach One Pump Module, and a Hach One Process pH or ORP Electrode
assembly. The system monitors a sample stream for its pH value within the range of 0 to
14, or its millivolt potential from -2000 to +2000 mV, and its temperature ranging from
0 to 60 °C. The system also indicates when preset high and low alarm limits are exceeded,
provides relay closures for external devices, and provides output currents to drive a
recorder and remote process control equipment. Each of these items are described in
detail in the following sections.
1.2 EC1000 pH/ORP Controller
The controller is menu driven with PID capability and is housed in a NEMA 4X/IP66
enclosure (see Figure 1 on page 18). It is set up to receive two current loop inputs from a
pH or ORP probe preamplifier, and to provide a continuous readout of the sample pH or
millivolt value as well as the sample temperature. Output capabilities of the controller
include two 4-20 mA outputs for recording and controlling pumps and optional RS-232C
and 20 mA current loop serial port. Alarm features include user programmable Alarm 1
and Alarm 2 setpoint selections for any one of the operating modes (pH, millivolt, or
temperature) with SPDT relay contacts. The alarm can be a combination of
operating modes:
(Example 1)
Alarm 1-pH High Alarm
Alarm 2-Temperature High Alarm
(Example 2)
Alarm 1-pH Low Alarm
Alarm 2-Temperature Low Alarm
The EC1000 Controller can be mounted up to 1000 feet from the electrode. The pump
module can be mounted up to 50 feet from the electrode.
1.3 Electrolyte Pump
Note: The electrolyte
pump is not used with the
self-pressurized Industrial
Process pH Electrode with
self-pressurized
electrolyte, Cat. No.
48276-00. See Section 1.6
Industrial Process pH
Electrode.
The pump used on this system is a low pressure linear peristaltic pump, which operates up
to 35 psi. The pump is housed in a NEMA 4X enclosure, and allows for a maximum of
50 feet separation from the electrode. It continuously pumps electrolyte through a free-
flowing junction in the electrode (500 mL of electrolyte [Cat. No. 24291-49]) lasts
approximately 30 days). The pump module contains a refillable electrolyte reservoir (see
Figure 2 on page 20).