INTER ELEKTRIK ELEKTRONIK LTD.
PM-DM/PM-DMR DIGITAL MULTIMETER USER GUIDE
1. INTRODUCTION
PM-DM/PM-DMR is microcontroller based device designed to measure current and
voltage of three phases and frequency of the system. Device also stores minimum and
maximum demands for both current and voltage and is capable to display these values to the
user when desired.
2. USING DIGITAL MULTIMETER
All connections have to be done according to
connection
schematic (Figure-1). When
power is applied for the first time in order to see current levels correctly current transformer
ratio have to be set to appropriate value. After this setting is done device will start displaying
correct values. L1, L2, L3 point to three phases and N indicates neutral connection. Outputs
of main current transformers have to be connected to k1, k2, k3 and l1,2,3 pins. This means
that “k” pins of CTs have to be connected seperately and “l” pins have to be wired together
and connected to l1,2,3 pin of R5-DM.
2.1. Setting Current Transformer Ratio
Press SET button. “CTR” and “SET” will be displayed on the lower side of display
consequently.Press “SET” button again. The lowest display will show current CTR value
(default is 5). Pressing “UP” or “DOWN” buttons enable user to adjust the desired CTR
value. Once “SET” button is pressed again the adjusted value will be saved in non-volatile
memory. Press “UP” button until “ESC” appears on the lowest display. Press “SET” button
again. After a short time device will start displaying current, voltage and frequency values on
the displays.
2.2. Setting Over Voltage Level
In normal operation, press “SET” button. Press “UP” button untill “UuL” “SEt” appears
on display. Pressing “SET” button again will indicate “Over Voltage Limit.” on the lowest
display Adjust the desired value and press “SET” button to save. Press “UP” button until
“ESC” appears on lowest display. Press “SET” button to Escape. After a short time device
will start displaying current, voltage and frequency values on the displays.
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