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On-line Hydrogen Peroxide Monitors shall be provided to continuously measure at the (Specify Locations). Each Hydrogen Peroxide Monitor shall consist of a direct measuring sensor, a clear constant-head flowcell, 25 feet of sensor interconnect cable with quick disconnect plug, and an electronic monitor housed in a NEMA 4X enclosure suitable for wall, pipe, or panel mounting.
The hydrogen peroxide sensor shall be a direct measuring polarographic sensor utilizing a special polymeric membrane to isolate the sensing electrodes from the sample and eliminate the potential for electrode contamination. The membrane shall allow hydrogen peroxide to diffuse into the sensor where it shall react with the sensing electrode, generating a signal that is linearly proportional to hydrogen peroxide concentration. The sensor assembly shall also contain a precision RTD temperature sensor to continuously measure sample temperature to allow temperature compensation of the measured hydrogen peroxide value. The hydrogen peroxide sensor shall be constructed with a quick disconnect receptacle to allow easy sensor servicing or exchange. Hydrogen peroxide sensors shall be supplied complete with at least 10 spare membranes, electrolyte, and a spare parts kit that includes all o-rings and special hardware.
The flowcell assembly supplied with the monitor shall be constructed of clear material allowing the condition of the sensor membrane to be inspected without removal of the sensor. The sensor shall slide easily into the side of the flowcell, with a double o-ring seal to prevent water leakage. Flow to the sensor shall be regulated automatically through a constant-head overflow arrangement. Hose barbs for sample inlet (1/4" I.D. tubing) and drain (1/2" I.D. tubing) shall be supplied as part of the flowcell.
The Hydrogen Peroxide Monitor electronic assembly shall be: (select one version below)
A. A loop-powered 2-wire instrument providing an isolated 4-20 mA output proportional to hydrogen peroxide into a maximum load of 575 ohms.
B. An AC powered instrument for operation on (specify either 115 VAC or 230 VAC) single-phase line power. The monitor shall provide two isolated 4-20 mA outputs configurable for hydrogen peroxide, temperature, or PID control. Analog outputs shall be both ground isolated and isolated from each other. AC powered hydrogen peroxide monitors shall also contain two SPDT relays.
C. A battery operated data logging monitor capable of operating from an internal 9 VDC battery. The monitor shall provide two 0-2.5 VDC outputs suitable for use by the internal data logger. The monitor shall operate for up to 4 days continuously on an alkaline battery and up to 10 days on a lithium battery.
The hydrogen peroxide monitor electronic assembly shall provide a variety of functions as follows.
1. Provide user selectable display of PPM hydrogen peroxide, process temperature, or PID % output on the main display. Main display variable shall be indicated with a minimum character height of 0.75” to allow easy readability up to 20 feet away.
2. Allow selection of operating ranges of 0-2 PPM, 0-20 PPM, or 0-200 PPM. Display ranges shall be configurable by operators, or the monitor may be configured for Auto-Ranging. The auto-ranging function shall automatically switch to the display range that provides the best resolution for any given operating level.
3. Provide the ability to use the 4-20 mA output for PID control. Proportional, Integral, and Derivative functions shall be user adjustable, and also provide for output hold when needed.
4. When operated on AC power, provide two isolated 4-20 mA outputs, with output spans programmable by the user for any segment of a display range.
5. Provide output hold and output simulate functions to allow for testing or remote receiving devices or to allow maintenance without disturbing control systems.
6. When operated on AC power, provide two SPDT relays. Relays shall be programmable for either control or alarm function, or relays may be assigned to diagnostic functions for use in indicating trouble conditions at a remote location.
7. Diagnostic functions shall be incorporated into the transmitter. The 4-20 mA output shall be capable of being assigned to safely rise to 20 mA, fall to 4 mA, or be left alone, during diagnostic failures. Diagnostic error messages shall be displayed in clear language; no confusing error codes shall be displayed.
8. When operated from a 9 VDC battery, provide data logging of hydrogen peroxide and temperature over programmable time intervals. Provide software with the data logger for easy data download to standard computers, with graphical and tabular viewing of data. Software shall allow export of data to standard spreadsheet programs.
The complete hydrogen peroxide monitor shall be supplied with spare parts and accessories for up to 2 years of operation. A minimum of 10 replacement membranes shall be supplied for the sensor.
The complete Hydrogen Peroxide Monitor shall be Series Q45H/84 as manufactured by Analytical Technology, Inc. or approved equal. |