Emerson MSM400 manual Diagnostic Parameters, EX-FACTORY System Features, Zero Setting Initial Zero

17.The value of the digit may now be incremented or decremented by pressing ⇑ ⇓.

			0
RL1 On Point%			0
00		.00	P411
	3

18.Press ENT to store the value. The highlighting will disappear. If an invalid number is entered then the display will revert to the last valid value.

19.The relay off point is programmed in the same way (all other numeric parameters are programmed in a similar way).

20.When programming is complete, return to the TOGGLE RUN menu and close the padlock.

21.Note; any programme changes will not alter the outputs, which remain frozen, until the TOGGLE RUN padlock has been closed.

5.3DIAGNOSTIC PARAMETERS

Apart from the user-settable parameters described above, there is another set of diagnostic parameters, which display measured or calculated data to analyse and optimise system performance. These have the prefix “D” and cannot be modified.

5.4EX-FACTORY SYSTEM FEATURES

The MSM400 Control Unit is supplied with default parameters that allow basic initial operation. The values and descriptions are listed in appendix two of this manual.

6.0CALIBRATION

There are several methods for calibrating the MSM400, AUTOCAL and MANUAL ENTRY, these together with some important basic principles are explained below. Calibration always comprises two stages, zero setting and span setting. Zero setting calibrates the system so that the control unit indicates 0% solids in clear liquid.

Span and lab value setting calibrates the system to monitor suspended solids accurately.

The recommended, simplest and most accurate method for calibrating the MSM400 is by using the AUTOCAL procedure, which is explained below.

6.1ZERO SETTING

INITIAL ZERO

The MSM400 has the facility to warn the operator that the sensors require cleaning. The first zero calibration will be stored in initial zero reference parameter, “Init zero ref”. Future zero calibrations are compared with this value and any significant change will produce a warning message like the one shown below.

	SET ZERO	0
In clear liquor		0

press ENT to set Sensor dirty

The actual difference required to produce this warning is programmed in dirty point (SETUP – ENGINEERING

–SENSOR LIMITS – Dirty Pt). The default value is 0, which disables this feature. To enable the feature it is suggested that a value of approximately 6 dB is entered.

Note: this warning feature is not active until the first zero calibration has been carried out.

To reset or clear initial zero value, ‘0’ must entered in Initial zero reference parameter (CALIBRATION – MANUAL ENTRY – ZERO REF – “Init Zero–1MHz” and “Init Zero–3MHz”, P123 & P124).

IP258

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