46
GMC-I Messtechnik GmbH
17
Operating and Display Elements
Test Instrument and Adapter
(1)
Control Panel – Display Panel
The following are displayed at the LCD:
• One or two measurement values as a three place numeric dis-
play with unit of measure and abbreviated measuring quantity
• Nominal values for voltage and frequency
• Circuit diagrams
• On-line help
• Messages and instructions
The display/control panel can be swiveled forward and backward
with the detented swivel hinge. The instrument can thus be set to
the optimum reading angle.
(2) Eyelets for the Shoulder Strap
The included shoulder strap can be attached at the right and left
hand sides of the instrument. You can hang the instrument from
your shoulder and keep both hands free for measurement.
(3)
Rotary Selector Switch
The following basic functions can be selected with this rotary
switch:
SETUP / I
N
/ I
F
/ Z
L-PE
/ Z
L-N
/ R
E
/ R
LO
/ R
ISO
/ U / SENSOR /
EXTRA / AUTO
The various basic functions are selected by turning the function
selector switch while the instrument is switched on.
(4)
Measuring Adapter
Attention!
!
The measuring adapter (2-pole) may only be used
together with the test instrument’s test plug.
Use for other purposes is prohibited!
The plug-on measuring adapter (2-pole) with the two test probes
is used for measurements in systems without earthing contact
outlets, e.g. at permanent installations, distribution cabinets and
all three-phase outlets, as well as for insulation resistance and
low-value resistance measurements.
The 2-pole measuring adapter can be expanded to three poles for
phase sequence testing with the included measurement cable
(test probe).
(5)
Plug Insert (country-specific)
Attention!
!
The plug insert may only be used together with the test
instrument’s test plug.
Use for other purposes is prohibited!
After the plug insert has been attached, the instrument can be
directly connected to earthing contact outlets. You need not
concern yourself with plug polarity. The instrument detects the
positions of phase conductor L and neutral conductor N and
automatically reverses polarity if necessary.
The instrument automatically determines whether or not both
protective contacts in the earthing contact outlet are connected
to one another, as well as to the system protective conductor, for
all types of protective conductor measurements when the plug
insert is attached to the test plug.
(6) Test Plug
The various country specific plug inserts (e.g. protective contact
plug insert for Germany or SEV plug insert for Switzerland) or the
measuring adapter (2-pole) are attached to the test plug and
secured with a threaded connector.
The control elements at the test plug are subjected to interference
suppression filtering. This may lead to a slightly delayed reaction
compared to direct instrument control.
(7) Alligator Clip (plug-on)
(8) Test Probes
The test probes comprise the second (permanently attached) and
third (plug-on) poles of the measuring adapter. A coil cable
connects them to the plug-on portion of the measuring adapter.
(9)
ON/Start
t
Key
The measuring sequence for the func-
tion selected in the menu is started by
pressing this key, either on the test
plug or at the control panel. Exception: If the instrument is
switched off, it can only be switched on by pressing the key at the
control panel.
This key has the same function as the
t
key on the test plug.
(10)
I
N
Key / I (at the control panel)
The following sequences are triggered
by pressing this key, either on the test
plug or at the control panel:
• Starts the tripping test after measurement of contact voltage
for RCD testing (I
N
).
• The
R
OFFSET
measurement is started within the
R
LO
/
Z
L-N
func-
tion.
• Semiautomatic polarity reversal (see section 5.8)
(11) Contact Surfaces
The contact surfaces are located at both sides of the test plug.
When the contact plug is grasped in the hand, contact is
automatically made with these surfaces. The contact surfaces are
electrically isolated from the terminals and from the measuring
circuit.
The instrument can be used as a phase tester for protection
class II devices!
In the event a potential difference of greater than 25 V between
protective conductor terminal PE and the contact surface, PE is
displayed (compare section 18.1, “LED Indications, Mains Con-
nections and Potential Differences”, beginning on page 51).
(12)
Test Plug Holder
The test plug with attached plug insert can be reliably secured to
the instrument with the rubberized holder.
(13) Fuses
The two type M 3.15/500G fuses (safety fuse FF 3.15/500G)
protect the instrument against overload. Phase conductor L and
neutral conductor N are fused individually. If a fuse is defective,
and if an attempt is made to perform a measurement which uses
the circuit protected by this fuse, a corresponding message
appears at the display panel.
Attention!
!
Severe damage to the instrument may occur if incorrect
fuses are used.
Only original fuses from GMC-I Messtechnik GmbH
assure required protection by means of suitable blowing
characteristics (order no. 3-578-189-01).
Note
The voltage ranges remain functional even if fuses have
blown.
(14) Holders for Test Probes (8)
(15/16) Current Clamp Connector Sockets
Only current transformer clamps offered as accessories may be
connected to these sockets.
