Teledyne gfc 7000ta operation manual Current Loop Output Adjustment, Edit

Operating Instructions Model GFC7000TA Carbon Dioxide Analyzer

FROM ANALOG I/O CONFIGURATION MENU

DIAG		ANALOG I / O CONFIGURATION
PREV NEXT			ENTR EXIT
DIAG AIO		AOUTS CALIBRATED: NO
< SET SET>		CAL		EXIT
Press SET> to select the analog output channel to be
		configured:
	DISPLAYED AS=		CHANNEL
	CONC_OUT_1 =		A1
	CONC_OUT_2 =		A2
	TEST OUTPUT =		A4
DIAG AIO		CONC_OUT_1 :5V, NO CAL
< SET SET>		EDIT		EXIT

Press to increase / decrease the analog output

by 100, 10 or 1 counts.

Continue adjustments until the voltage measured at the output of the analyzer and/or the input of the recording device matches the value in the upper right hand corner of the display to the tolerance listed in Table 6-20.

The concentration display will not change. Only the voltage reading of your voltmeter will change.

DIAG AIO					CONC_OUT_1	RANGE: 5V
		SET>		EDIT			EXIT
DIAG AIO					CONC_OUT_1 REC OFS: 0 mV
< SET SET> EDIT							EXIT
DIAG AIO CONC_OUT_1 AUTO CAL: OFF
	< SET SET>				EDIT		EXIT
DIAG AIO				CONC_OUT_2 CALIBRATED: NO
< SET			CAL				EXIT
		DIAG AIO			CONC_OUT_1 VOLT–Z : 0 mV
		U100		UP10	UP DOWN	DN10 D100 ENTR EXIT
		DIAG AIO			CONC_OUT_1 VOLT–S : 4500 mV
		U100		UP10 UP DOWN		DN10 D100 ENTR EXIT
		DIAG AIO CONC_OUT_1 CALIBRATED: YES
		< SET			CAL		EXIT

If AutoCal is ON, go to

Section 6.7.3

EXIT ignores the new setting.

ENTR accepts the new setting.

6.13.4.4. Current Loop Output Adjustment

A current loop option is available and can be installed as a retrofit for each of the analog outputs of the analyzer (s 5.2). This option converts the DC voltage analog output to a current signal with 0-20 mA output current. The outputs can be scaled to any set of limits within that 0-20 mA range. However, most current loop applications call for either 2-20 mA or 4-20 mA range. All current loop outputs have a +5% over-range. Ranges with the lower limit set to more than 1 mA (e.g., 2-20 or 4-20 mA) also have a -5% under-range.

To switch an analog output from voltage to current loop after installing the current output printed circuit assembly, follow the instructions in Section 6.13.4.4 and select CURR from the list of options on the RANGE menu.

Adjusting the signal zero and span values of the current loop output is done by raising or lowering the voltage of the respective analog output. This proportionally raises or lowers the current produced by the current loop option.

Similar to the voltage calibration, the software allows this current adjustment to be made in 100, 10 or 1 count increments. Since the exact current increment per voltage count varies from output to output and from instrument to instrument, you will need to measure the change in the current with a current meter placed in series with the output circuit (Figure 6-16).

Teledyne Analytical Instruments 131