Eutech Instruments 1000 series 1/4 DIN conductivity and resistivity controllers have an advanced set-up mode to easily customize features. Their 0 to 2000 second selectable time delay and adjustable set point hysteresis bands mean you can tailor control relay action to meet your needs.
Each unit is selectable for isolated 0-20 or 4-20 mA transmitter/recorder output; 110 or 220 VAC; normally open or closed relays; and manual or automatic temperature compensation. The compact 1/4 DIN size fits into standard panel cutouts. The IP54 rated front panel keypad is weather resistant. Includes mounting hardware.
- A menu-driven program that simplifies set-up
- Large dual display LCD shows con- ductivity (resistivity) and temperature along with clear multiple annunciators
- Two set point, two SPDT relay operation for lo/lo, lo/hi, hi/lo or hi/hi control
- 0 to 2000 second time delay adjustment on all relays— minimizes false alarms
- Separate alarm relay alerts you to set points exceeded for a specific length of time or a failed temperature sensor
- Separately adjustable high and low set point hysteresis bands prevent rapid contact switching if your mea- sured value is fluctuating near the set point
- Adjustable temperature coefficient from 0.00 to 10.00% per °C lets you input your solution’s true temperature correction for higher accuracy
- Choice of 0.01, 0.1, 1.0 or 10.0 cell constants for accurate readings in any solution
- 0-20/4-20 mA transmitter/recorder output for remote monitoring and hard copy recording
- Protection against electromagnetic interference—galvanically isolated output
- Push button keypad gives you fast access to one-point calibration, switchable manual or automatic temperature compensation, and call up to view set points
- Two level password protection— first level allows quick access to calibration; second level lets you change set up parameters
- LED indicators signal control activities to monitor controller status from a distance
- Nonvolatile memory maintains setup even when power fails
Typical Measurement and Control System
A typical measurement system consists of:
- power source
- the OAKTON 1000-series controller
- a conductivity (or resistivity) cell with or without built-in temperature sensor (Pt 100 or 1000)
- installation hardware for cell
- an appropriate measurement cable
- a final control element such as a pump or valve
- a recorder (optional)
- a visual and/or audible alarm (optional)
Unit dimensions
The field-tested control panel housing is 3.78" x 3.78" (96 x 96 mm).
The front panel meets protection class IP 54.
Back panel
The back panel consists of two different connectors: the 17-way PCB edge connector and the 5-way screw terminal connector.
Electrical Connections
CAUTION: Electrical shock hazard! Make sure to remove AC power to the controller before wiring input and output connections, and before opening the controller housing.
- VAC live wire
- VAC neutral wire
- VAC protective ground wire
NOTE: Power is selectable for 110 or 220 VAC via an internal jumper.
Factory setting is indicated on the label on top of the controller.
- Low set relay resting position
- Low set relay common
- Low set relay working position
- High set relay resting position
- High set relay common
- High set relay working position
- Alarm relay resting position
IMPORTANT: The alarm relay functions as an “Active Low” device; e.g.
switches OFF under alarm condition. Therefore the alarm display device should
be connected to the 'NC' contacts of the relay.
- Alarm relay common
- Alarm relay working position
- Hold function switch terminal 1
- Hold function switch terminal 2
- No connection
- 0/4 - 20 mA for – current connection
- 0/4 - 20 mA for + current connection
Cell/temperature sensor connections
18. Pt100/Pt1000 lead 1 terminal
19. Pt100/Pt1000 sense lead terminal
20. Pt100/Pt1000 lead 2 terminal
NOTE: If using a two-wire RTD, short terminal 19 to terminal 18.
NOTE: Pt100/Pt1000 is selectable via an internal jumper setting. Factory default
is Pt100.
the RTD type.
21. Cell lead 1
22. Cell lead 2
HOLD function
The HOLD function lets you force the relays to their resting position by applying a contact closure across terminals 13 and 14.
When the HOLD function is activated, the HOLD indicator will appear in the upper left corner of the display.
Typical applications:
Float or level switch: Connect to a float switch in your reagent feed tank to shut down pumps or tanks when out of reagent.
Flow switch: Connect to a flow switch to shut down pumps or valves when the process stream is shut down.
Dual conductivity control: Use for dosing two chemicals in stepwise addition.