Chauvin Arnoux DTR 8510 Notice De Fonctionnement page 62

5.2.3. VT/PT EXCITATION CURRENT
Excitation current, displayed in milli-amperes (mA) is the RMS current in the Primary (H) winding due to test excitation. The load-
ing on the Secondary (X) winding due to the DTR
„ The DTR 8510 uses a maximum of 32 Vrms excitation voltage for testing. The displayed excitation current will almost always
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be a small fraction of transformer no-load excitation at full (rated) voltage. Most transformers will require less than 100 mA.
„ If you are presently using a ratiometer that employs secondary (X) side excitation (e.g. common hand-cranked instruments)
in step-up mode, the current may be much higher than what the DTR
„ This is normal and results directly from the fact that in most step-down transformers, the Primary (H) side has a much higher
impedance than its associated Secondary (X) winding.
5.2.4. VT/PT CONTINUITY TEST
The Continuity Test function of the DTR
resistance connections, open circuit breakers and blown fuses. When selected, the DTR
Secondary (X) and Primary (H) cables.
„ The DTR 8510 will indicate OPEN for circuits > 4 kΩ and CONT for circuits < 4 kΩ. Check these values. A small fraction of
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transformers (High inductance or high winding Ohmic DC resistance) may appear open.
„ The instrument checks for Secondary (X) connections first. Even if it is found open, it continues to check Primary (H) connec-
tions. Regardless of the outcome, the instrument proceeds to perform pre-test checks. Following the pre-test checks, if either
X or H or both were found to be OPEN, the instrument will display the appropriate error message. Pressing the TEST button
again will start a new Continuity test (assuming the user fixed the connection problem) again. If it passes the Continuity test,
Ratio test will be executed.
„ Transformers with winding arrangement multiple, parallel paths (e.g., Delta type) may read CONT even if one or more wind-
ings may be OPEN.
5.2.5. CT TEST
In this paragraph, an example of running a test using the following configuration (see § 4.3 for how to configure the instrument)
is shown:
„ Set Date/Time: July 4, 2010. 6:00 PM
„ Set values in Nameplate:
Primary Voltage:19920; Secondary Voltage: 7200
„ Select Type: VT/PT
„ Select Test Mode: CONT/Ratio
„ Storage Mode: Manual
„ Set Filter: Normal
„ Set Language: English
Note: CT test does not allow a CONT/Ratio option. It only runs a Ratio test.
WARNING: The DTR
completely disconnected from AC power and is fully discharged.
8510 is negligible.
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8510 serves as a useful means of identifying open primary and secondary windings, high
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8510 is designed for use on de-energized ("dead") transformers only. Make sure the test sample is
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8510 displays.
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8510 checks for continuity between its
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