The Hanna Instruments HI 9910 Wall mounted Industrial Grade 0 to 14 pH Controller with Single Set point also provides for an alarm relay. The alarm is activated when the measurements stray away from the set point by a predetermined value in the 0.5 to 2.5 pH range. A maximum dosing time from 1 to 10 minutes can also be set, after which the alarm is activated to warn of an abnormality. The Hanna Instruments HI 9910' s alarm can be configured in either normally-closed or normally-opened state. The Hanna Instruments HI9910 also provides an isolated output signal which is user selectable between 0-20 or 4-20 mA. A dial on the front panel renders manual temperature compensation fast and easy. For automatic temperature compensation, hook up a three wire Pt100 to the controller. To speed up wiring, the Hanna HI 9910 comes with extractable terminal modules. Once wired up, the compartment containing the connections is protected behind a fire-retardant ABS panel. Several LED' s show whether the set point or alarm relays are activated from a distance.
