Advanced math functions allow for complex configurations to be carried out and the results annotated using custom messages to print along side the raw data. Process variables including messages can be archived to an optional integral card reader. The units can be programmed on site via the user interface (featuring a ‘secret-til-lit’ keyboard, or a configuration file can be transferred using a PCMCIA card.
Display
As well as displaying the process variables as a numeric value the 4181M/4250M can provide bargraph indication. The display will automatically cycle through configured PV’s, within the selected display group configured.
Configuration
User configuration is password protected. In addition to instrument configuration selected fields can be defined for operator access. These fields will be enabled in the operator access menu.
Adaptive recording
At slow chart speeds it is possible that the input circuit, between chart increments will pick up a spike or other brief disturbance in the measured signal, but that this disturbance will not appear on the chart, even though they may trigger an alarm. With adaptive recording enabled, if a sudden change in the input signal is detected, the recorder will place an additional dot on the chart without the chart being moved. This means that even at the lowest chart speed, unexpected signal changes can still be trended.
Analog output
If required, an input signal or the resulting calculation of a math channel can be retransmitted to another device.