The BL931700 is a compact single setpoint pH controller designed for applications where space and/or cost are important. It's adjustable dosing relay may be configured to dose above or below a pH setpoint. Users may choose from automatic or manual dosing modes allowing for easy maintenance and troubleshooting. The device contains a high impedance pH input and may be used with any pH electrode that has a standard BNC connector.
The BL931700 model offers a manual two-point calibration with pH values displayed out to two decimal places.
A normally open contact may connect to a level controller or flow monitor. This safety feature may be used to prevent continuous dosing in the event of specific or undesired system conditions.
The BL931700 features a dosing relay which may be configured to dose above or below a user programmable pH setpoint.
The mini controller may be programmed to deactivate a valve, pump, or connected device if its activation continues over a selected time; adjustable from 5 to 30 minutes.
With the flick of a switch, normal "Autoin. operation may be overridden turning your connected device "Offin. from operation or always "On.in.
The BL931700 features a 4 - 20 mA analog output for connection to a data logger, chart recorder, or other device.
An included matching pin option helps protect the sensor from ground loop effects that may lead to erratic readings or system damage.
The mini controller is protected for up to a 2A load from the connected pump or device.
Quick-connect terminal blocks provide for easy connection to power, communication, dosing control, or sensors.
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Front ViewInstallation cut-out dimensions are provided as well as outside panel dimensions. | Side ViewAdjustable location brackets allow the controller to slide easily and securely into place. |
Specification | Detail |
---|---|
SKU | BL931700 |
pH Range | 0.00 to 14.00 pH |
pH Resolution | 0.01 pH |
pH Accuracy (@25°C/77°F) | ±0.02 pH |
Calibration | manual, through offset and slope trimmers |
Dosing Relay | maximum 2A (fuse protected), 250 Vac, 30 VDC |
Dosing Selection | acid or alkaline contact open=acid dosage=relay ON if measurement > |
setpoint contact closed | alkaline dosage=relay ON if measurement < setpoint |
Setpoint | adjustable from 0 to 14 pH |
Overtime | adjustable, typically from 5 to approximately 30 minutes |
Recorder Output | 4 to 20 mA, accuracy ±0.20 mA, 500 Ω maximum load |
Input Impedance | 10^12 Ohm |
Power Supply | BL931700-0: 12 VDC adapter (included) BL931700-1: 115/230 VAC 50/60Hz |
Dimensions | 83 x 53 x 99 mm (3.3 x 2.1 x 3.9') |
Weight | BL931700-0: 200 g (7.1 oz.) BL931700-1: 300 g (10.6 oz.) |
Ordering Information | Supplied with mounting brackets, transparent cover and instruction manual. |
Recommended Probe | HI1001 PVDF body pH electrode with 1/2in. NPT thread, BNC connector and 3 m (9.8') cable for continuous flow-thru monitoring (not included). |