Gossen-metrawatt Metrahit 18CIS User Manual

Operating Instructions

METRA18C

Calibrator

3-348-715-15 5/1.02

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

9)									10)											7)
8)																							6)
1)
																			5)
2)																					4)
																						3)

11)

16)

17)

12)

13)

18)

19)							14)

15)

2	GOSSEN-METRAWATT

Operating Instructions

(1)LC display

(2)ON/OFF key, cursor right ENTER

(3)Key for digit increment, increasing step

(4)Key for digit decrement, decreasing step

(5)Key for cursor left, EXIT

(6)Functions selector for basic functions

V, mV									= V, mV-source
									= frequency, pulse
°C									= thermocouple (TC) simulation
°C									= RTD sensor simulation
									= resistance simulation
mA									= mA-SOURCE
mA									= mA MEAS, mA SINK

(7)Jack for plug type mains unit

(8)Jacks with automatic interlocking

LC Display

1)5-digit numeric display, 1st digit indicates type of thermocouple

2)Cursor field

3)Menu guidance symbols for basic functions SOURCE = source, i.e. simulation of signals

SINK = sink, i.e. for simulating a 2-terminal transmitter

4)Measurement units for measured values

5)Menu guidance symbols

TC = basic function ”°C “, for thermocouple simulation TREF = setting the reference temperature

6)Type of simulated RTD sensor, e.g. Pt100 in the basic function ”°C “

7)FREQ = pointing to the basic function ” “ = frequency or

pulse output

8)Menu guidance symbols for types of signal output NUM = numerical entry for the output signal INT = intervals, output in N steps

RAMP = ramp output

MEM = memory, output from the non-volatile memory

9) N?

= request for entry of the number of steps in output type INT

10)Menu guidance symbols for output method MEM using MAN = number of steps by manual key action

AUT = number of automatic steps with selectable time per step

11)min:s = flashing menu guidance symbol for time entries

12)Menu guidance symbols for output method MEM using OUT = output from memory

IN = input to memory

13)Number of the memory value or number of the procedure

14)Menu guidance symbols for permissible key operations EXIT = key (5) for EXIT function (Esc)

ENTER = key (2) for ENTER function

=keys (2) and (5) moving the cursor to the right (2) or to the left (5)

=keys (3) and (4) for menu selection on the same level modifying digits or step function

15)MIN and MAX simultaneously

pointing out the ranges with selectable lower and upper range limits MIN or MAX flashing

Menu guidance symbol when entering the lower range limit (MIN) or the upper range limit (MAX) for output types INT and RAMP

MAX flashing

Upon entering the upper range limit during current measurement

16)Menu guidance symbol for REMOTE operation via the serial interface

17)ERROR ! = warning symbol for error states

18)	=		pointing out the inhibited automatic cut-out
19)		=	indication of "battery low" or for battery voltage indication
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Contents
		Page
1	Safety Features and Precautions .......................................	5
2	Putting into Operation ........................................................	7
3	General Advice for Operation .............................................	9
3.1	Key Panel .............................................................................	9
3.2	Menu Structure and Key Operations .....................................	10
3.3	LC display ..........................................................................	11
3.4	Operating Assistance by the LC Display ...............................	13
3.5	Entering Digits ....................................................................	13
3.6	Non-Volatile Saving of Menu Positions and Configurations ....	14
4	Types of Output Signals ...................................................	15
4.1	Menu Structure ..................................................................	15
4.2	Numerical or Manual Entries for the Output Signal (NUM) ......	15
4.3	Intervals, Output in N Steps (INT) .........................................	15
4.4	Output as Periodic Ramp (RAMP) .........................................	18
4.5	Output from the Non-Volatile Memory (MEM) ........................	20
4.6	Output by Prozedures Saved in the Non-Volatile Memory ......	22
4.7	Output via the Serial Interface (REMOTE) ..............................	23
5	Basic Functions ................................................................	25
5.1	General Notes ....................................................................	25
5.2	Supervisory Circuits ............................................................	25
5.3	[V, mV], Voltage Source ......................................................	28
5.4	, Pulse Generator ...................................................	28
5.5	[°C], Thermocouple Simulation ............................................	31
5.6	[ C], RTD Sensor Simulation ...............................................	33
5.7	[ ], Resistance Simulation .................................................	34
5.8	, Current Source .........................................................	34
5.9	Current Measurement [mA] .................................................	35
5.10	, Current Drain, Simulation of a Transmitter
	with two Leads ...................................................................	36
6	Technical Data .................................................................	38
7	Maintenance ....................................................................	41
7.1	Batteries ............................................................................	41
7.2	Housing .............................................................................	42
8	Appendix ..........................................................................	43
8.1	Errors in [°C] in Thermocouple Simulation ............................	43
9	Repair and replacement parts service .............................	44
10	Product Support .................................................................	44

4	GOSSEN-METRAWATT

1 Safety Features and Precautions

This chosen instrument will provide a high degree of safety.

The calibrator is designed and tested in accordance with the safety regulations IEC 61010-1 / DIN VDE 0411.

When used in accordance with the regulations, it will ensure the safety of the operating personnel and protection of the instrument. However, safety is not ensured when the instrument is operated improperly or treated carelessly.

To maintain a proper state of safety, and to ensure a hazard-free use, the operating instructions must be read carefully and completely prior to the use of the instrument, and all points in the operating instructions must be complied with.

For the purpose of personal safety, and for the protection of the instrument, the calibrator is provided with automatic jack interlocking.

This is coupled with the functions selector, and makes only those jacks accessible that are required for the selected function. Furthermore, it inhibits switching into wrong basic functions when the measurement leads are plugged in. Hence, only the correct polarity of the connection as marked at the jacks need be verified.

Please observe the following safety precautions:

Attention!

The meter has been designed for safe use when not connected to circuits which conduct hazardous contact voltages of greater than 42 V to earth.

•Never mistake the calibrator for the similarly housed multimeters. The calibrator is distinguished from the multimeter by its YELLOW jack sleeves and leads; the multimeter has red jack sleeves and red and black leads.

•When intending to connect the instrument with a circuit, the absence of hazardous touch voltages must be verified first, if necessary with a multi-meter.

•Please observe the maximum permissible voltages for the protection of the instrument stated at the jacks.

Except during operation for resistance simulation and mA-SINK, the connected signal circuits should not feed currents or voltages back into the calibrator.

In order to prevent major damages to the instrument when extraneous voltages (within the permissible limits) are applied, the measuring circuit for mA-SINK and mA-SOURCE is provided with a PTC resistor overload protection that turns these measuring circuits into high resistance ones during the overload period when higher currents occur during a fault.

Warning!

The instrument shall not be used in explosion endangered zones or inserted in self-protected circuits.

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5

Repairs, Exchange of Parts, and Calibration

Voltage-carrying parts can be found exposed when the instrument is opened. The instrument must be disconnected from measuring circuits before any repair, exchange of parts or calibration. When repair or calibration work under voltage and with an opened instrument is unavoidable, then this shall only be carried out by a skilled person aware of the dangers that may arise.

Faults and Extraordinary Loading

When a continued hazard-free use of the instrument is doubtful, it must be made inoperable and protected against inadvertent use.

A hazard-free use is no longer ensured when

•the instrument shows visible damage,

•the instrument no longer operates,

•the instrument has been kept in storage under adverse conditions,

•the instrument has been subjected to severe transport conditions,

•measurement leads or probe tips are damaged.

6	GOSSEN-METRAWATT

2 Putting into Operation

Inserting Batteries

3 alkaline cells size IEC LR6, 1.5 V / 2.2 Ah are supplied inserted in the instrument. It is ready for operation.

Please note Section 7.1 Maintenance – Battery" prior to operating the instrument.

In there, the additional statement is made that externally rechargeable batteries may be used.

One of the accessories is a plug type mains power supply that permits driving the instrument with power from the mains.

The internal batteries will be disconnected from the circuit when the plug is inserted into the instrument. Thus, they cannot draw power from the mains power supply.

Only this plug type power supply that is matched to the instrument in respect of voltage and power, may be used.

Switching the Instrument On

Press the "ON/OFF" key (2).

The switched-on state is acknowledged by a signalling tone.

Pressing the "ON/OFF" key (2) for a short period will cause the firmware version stored in the EPROM and, subsequently, the battery or power supply voltage to be briefly displayed during switching on process, before the instrument becomes operational in the operational mode selected with the functions selector (6).

Pressing the "ON/OFF" key (2) for a longer period will cause all segments of the LC display (1) shown in Section 3.3 to be displayed.

The instrument becomes operational when the key is released.

Attention!

The following can occur when the charge state of the batteries is low: the internal battery voltage supervision causes the instrument

–not to switch on

–to switch off immediately afterwards

–to switch off when the output is loaded or

the internal change-over selects a higher auxiliary voltage (e.g. 10/15 V range, 20 mA / 750 ).

See also Section 5.2 and Section 7.1.

In this case, the batteries should be replaced in accordance with Section 7.1 or

the plug type mains unit may be used, if possible.

When the instrument is operational, the last menu position will be saved in the non-volatile memory (NVRAM) before the instrument is switched off.

Provided the position of the functions selector has not been changed during the switched-off period, the instrument will, immediately after switching on, revert to the menu position used prior to switching off.

Jumping to the highest menu level is achieved in the simplest way by turning the functions selector into an adjacent position and back.

This switching process is also recommended after wrong menu operations or uncertainties in respect of the actual menu setting.

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Note!Electrical discharge and RF interference may cause incorrect readings and disrupt the measuring sequence.

Then the instrument should be switched off and switched on in a different position of the functions selector; this will reset the operation of the instrument.

Should this attempt fail, then the batteries should be disconnected from the circuit for a short period. This can be done by plugging in the power supply without opening the instrument.

Prior to opening the instrument, the latter must be disconnected from the circuit to be measured, and Section 7 "Maintenance" must be observed!

Automatic Switching Off

The instrument is switched off automatically, if none of the keys or the function selector have been activated for a period of approx. 10 min.

Inhibiting the Automatic Switching Off

The instrument can be set to "PERMANENTLY ON".

When switching ON, the "ON/OFF" key (2) and the yellow "ESC" key (5) must be pressed simultaneously.

Note:

The function "PERMANENTLY ON" is indicated by the symbol on the LC display (1).

Automatic switching off is inhibited also when the instrument is set to REMOTE operation via the serial interface in accordance with Section 6.

Switching the Instrument Off

Press the ON/OFF key (2) for at least 1 second.

8	GOSSEN-METRAWATT

3 General Advice for Operation

3.1 Key Panel

The control operations required for the comprehensive facilities for signal outputs are executed by using only the four keys (2) to (5) after the basic function has been selected by means of the functions selector. Their effect depends on the actual setting of the menu position, but follows a general control principle described in Section 3.2.

ON/OFF •				Switching ON/OFF
				ENTER-function,e.g.
(1)			•	Entering a sub-menu
			•	Loadng an entered number digit
			•	Moving the cursor to the right
				when entering digits
			•	Incrementing a digit
			•	Stepping to an adjacent menu
(2)				on the same menu level
			•	Starting ramps and interval steps
				upwards and stopping them
			•	Jumping back to the preceding pro-
				gram step (RECORD) under the basic
				function PROCEDURES in accor-
				dance with Section 4.6
			•	Decrementing a digit
			•	Stepping to an adjacent menu
(3)				on the same menu level
			•	Starting ramps and interval steps
				downwards and stopping them
			•	Jumping forward to the next program
				step (RECORD) under the basic func-
				tion PROCEDURES in accordance
				with Section 4.6

Esc EXIT-function, i.e.

•Back to the higher menu level

•Terminating ramps, automatic interval

(4)	stepping, frequency and back to the
	higher menu level
	• Moving the cursor left when entering
	digits

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3.2 Menu Structure and Key Operations

The menu structure is designed on a uniform concept for nearly all basic functions.

The highest menu level comprises the basic functions that can be selected with the functions selector (6). All other operations are executed by using the 4 keys in accordance with a structure shown in Figure 1.

1

enü 1

ü 2

ü A

Menu

Menu 2

Menu A

1)

Esc

Esc

Esc

Menuü 11.1.1

Menunü 1.12.1

Menuü 1.B.1

Menüsu

X..Y

2)

X=2--A,A,Y=1-B

Esc

Esc

Esc

Esc

Other sub-me

us depending o the type of operation and output

Weitere Untermenüs je nach Betriebsund Ausgabeart

1)

1. Key panel menu level of the selected type of operation (ranges or type of sensor)

1)

2)

1. Tastatur-Menüebene der eingestellten Betriebsart (Bereiche oder Sensortypen)

2. Key panel menu level, method of output for the selected range or type of sensor

2)

2. Tastatur-Menüebene, Ausgabeart für gewählten Bereich oder Sensortyp

Figure 1 Concept of the Menu Structure

The basic function “ “ and the “mA MEAS” function are excepted from this menu structure.

Furthermore, the following is carried out between the 1st and 2nd menu levels in the basic functions:

”°C “ selection of the internal and external reference temperature and its entry, as well as

”°C “ entering the lead resistance

The following functions are associated with the various menu levels:

	1st Menu Level		2nd Menu Level	Other Menu Levels
	Selection of the signal	Selection of the method
	ranges or of the types of	of signal output:
	sensor depending on the	NUM = numerical		Manual numerical input
	basic function selected
				of the output value
	with the functions selector
		INT-	= subdivision of a	Input of the lower and upper
		specified range into a number		range limits (these are already
		of similar steps. The sequence		defined for the standard ranges
		can be manual (MAN) or auto-		0 ... 10 V, 0/4 ... 20 mA)
		matic (AUTO) with an adjustable		as well as entering the number
		time per step		of steps. Under AUTO:
				entering the time per step,
				starting and stopping steps
		RAMP	= output as an	Entering the lower and upper
		ascending or descending ramp		range limits as well as ramp
		with a dwell time at the upper		duration (						) and dwell
		and lower range limits		time (						) Starting and
				stopping the ramps
		MEM = output of 10 signal		Entering
		values per range or type of		signal values into the
		sensor that have been saved		non-volatile memory (NVRAM)
		earlier in the non-volatile		and output from the NVRAM
		memory (NVRAM)

10	GOSSEN-METRAWATT

The menu structure with the functions on the menu levels is printed in an summarizing format (Figure 2) on the underside of the housing.

1st menu level for the key panel

2nd menu level for the key panel Other menu levels

Figure 2 Illustration of the Menu Structure Printed on the Underside of the Housing

3.3 LC display

The LC display is an important element in the user guidance in which, in addition to numerical displays, various symbols show the actual menu position and give advice on actions to be taken.

Figure 3 shows the LC display with all its symbols that are displayed during a segment test mentioned in Section 2.

8									9	10 11	7	kF
16
17												6
kF
12												5
1
												4
13
2												kF
18					19	15			14			3

Figure 3 LC Display

The symbols have the following significance:

1)5-digit number display,

1st digit for an additional indication of the type of thermocouple

2)Cursor field

3)Menu guidance symbols for basic functions SOURCE = source, i.e. simulation of signals

SINK = sink, i.e. for simulating a 4-terminal transmitter MEAS = measuring the current signal 0 ... 24 mA DC

4)Measurement units for measured values

5)Menu guidance symbols

TC = basic function “°C “, for thermocouple simulation TREF = setting the reference temperature, (internal or external

cold junction)

6)Type of simulated RTD sensor, e.g. Pt100 in the basic function “°C “

7) FREQ = pointing to the basic function ”								“ = frequency
or pulse output
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8)Menu guidance symbols for methods of signal output NUM = numerical entry for the output signal INT = intervals, output in N steps

RAMP = ramp output

MEM = memory, output from the non-volatile memory

9)N? = flashing menu guidance symbol when entering

the number of steps in output method INT

10)Menu guidance symbols for output method MEM

MAN = number of steps using manual key operation

AUT = number of automatic steps with selectable time per step

11)min:s = flashing menu guidance symbol for time entries

for method output INT, AUT and RAMP

12)Menu guidance symbols for method output MEM OUT = output from memory

IN = entry for memory

13)7-segment digit indicating the number of the memory value output method MEM or the procedure No. under the basic function PROCEDURE

14)Menu guidance symbols for permissible key operations EXIT = key (5) for EXIT function (Esc)

ENTER = key (2) for ENTER function

=keys (2) and (5) moving the cursor to the right (2) or to the left (5)

=keys (3) and (4) for menu selection on the same level, changing digits or step function

15)Menu guidance symbols

MIN and MAX simultaneously

pointing out the ranges with selectable lower and upper range limits on the 1st menu level of the basic functions ”V, mV, mA“

MIN or MAX flashing

menu guidance symbol when entering the lower range limit (MIN) or the upper range limit (MAX) for output method INT and RAMP

MAX flashing

upon entering the upper range limit during current measurement

16)Menu guidance symbol for REMOTE operation via the serial interface

17)ERROR ! = warning symbol for error states

18)	= symbol for "PERMANENTLY ON“.
19)	=	indication of "battery low" or for battery voltage indication
		after switching on
kF)	=	no function, symbols are not used.

12	GOSSEN-METRAWATT

3.4 Operating Assistance by the LC Display

Symbols are displayed on the LC display as a function of the selected menu to support the user of the instrument during the control operation as follows:

•Where am I ?

i.e. confirmation of the basic function and the data functions selected with keys, e.g. output method and type of quantities to be entered

•Keys for further processing ?

Key operations required for continuing a process are indicated by the menu guidance symbols (14) in accordance with Section 3.1 Inadmissible key operations are pointed out by a single tone pulse.

•Special events, e.g.

= low battery voltage,

ERROR ! = wrong operational states, pointed out in more detail by assisting text.

3.5 Entering Digits

Manual entering of numerical values is carried out in the following manner

= moving the cursor to the right (2).

When the cursor is already positioned beneath the last digit, then this key has the function ENTER for saving the entered value.

= incrementing a digit (3).

Pressing this key briefly will increment the value of the digit by 1. Keeping this key pressed will increase the indicated value by 1 every 0.4 sec. from the cursor position to the left after a short tone pulse.

= Decrementing a digit (4).

Pressing this key briefly will decrement the value of the digit by –1. Keeping this key pressed will decrease the indicated value by 1 every 0.4 sec. from the cursor position to the left after a short tone pulse.

= moving the cursor to the left (5).

When the cursor is already positioned beneath the first digit, then this key has the function EXIT, i.e. the next pressing causes a jump to the next higher menu level.

•When a digit is incremented from 9 to 0, the next digit to the left is increased by +1. When decrementing a digit from 0 to 9, the next digit to the left is decreased by –1 (counting function).

•Each digit entry is limited within a maximum and a minimum in accordance with the technical data. A change of a digit that would lead to a violation of these limits, is signalled by a short tone. In this case, the numerical value will be set to the range limit.

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13

Example of Entries

Entering the upper interval limit (MAX) = 12 V in the basic function, "V, mV SOURCE" in the range 0...15 V under the output method "Intervals" (INT). See also Section 4.2.

Key Operation

Display

Notes

Various key operations

Ready for entering

see Section 4.2

the MAX value;

Cursor and MAX are

flashing

Cursor to the left;

Further movement to the left

causes a jump back to entering

the MIN value

Further incrementing would set

the value to the upper range

limit of 15 V after a short tone

Moving the cursor to the right

MAX set to 12 V

2x

Key (2) now has the function

3x

of ENTER.

Pressing key

would set

the value to 11.999 V

Ready for entering the number

N of intervals

"N?" flashes

3.6 Non-Volatile Saving of Menu Positions and Configurations

The METRAHit 18Cis fitted with a non-volatile memory (NVRAM) in which current menu positions (LAST MENU) and configurations remain saved after switching off. When switched off, the NVRAM is supplied with power from 3 small batteries.

During a battery replacement in accordance with Section 7.1, a special supporting capacitor acts in a bridging function for 3 minutes.

As mentioned in Section 2, the instrument will, when switched on again, resume exactly the last menu position prior to switching off, provided the functions selector position has remained unchanged. This saves time-consuming key operations for entering complex menus. Furthermore when used on site, this will reduce the load on the batteries, when the instrument is switched off whenever it is not in active use.

In all basic functions, the configurations once set for a range or type of sensor, will be saved in the non-volatile memory when the instrument is switched off, e.g. MIN/MAX values in INT, RAMP, RAMP timing.

14	GOSSEN-METRAWATT