Brymen TBM157 User manual

USER'S MANUAL
TBM157 & TBM357
3-Phase PowerClampTM

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1) SAFETY
This manual contains information and warnings that must be followed for operating the
instrument safely and maintaining the instrument in a safe operating condition. If the
instrument is used in a manner not specified by the manufacturer, the protection
provided by the instrument may be impaired.
The meter protection rating, against the users, is double insulation per IEC61010-1 2nd
Ed., EN61010-1 2nd Ed., UL61010-1 2nd Ed., CAN/CSA C22.2 No. 61010.1-0.92,
IEC61010-2-032, EN61010-2-032 & UL61010B-2-032:
Category CAT III 600V AC & DC.
PER IEC61010 OVERVOLTAGE INSTALLATION CATEGORY
OVERVOLTAGE CATEGORY II
Equipment of OVERVOLTAGE CATEGORY II is energy-consuming equipment to be
supplied from the fixed installation.
Note – Examples include household, office, and laboratory appliances.
OVERVOLTAGE CATEGORY III
Equipment of OVERVOLTAGE CATEGORY III is equipment in fixed installations.
Note – Examples include switches in the fixed installation and some equipment for
industrial use with permanent connection to the fixed installation.
OVERVOLTAGE CATEGORY IV
Equipment of OVERVOLTAGE CATEGORY IV is for use at the origin of the installation.
Note – Examples include electricity meters and primary over-current protection
equipment.
TERMS IN THIS MANUAL
WARNING identifies conditions and actions that could result in serious injury or even
death to the user.
CAUTION identifies conditions and actions that could cause damage or malfunction
in the instrument.

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WARNING
To reduce the risk of fire or electric shock, do not expose this product to rain or
moisture. The meter is intended only for indoor use.
To avoid electrical shock hazard, observe the proper safety precautions when working
with voltages above 60 VDC or 30 VAC rms. These voltage levels pose a potential
shock hazard to the user.
Keep your hands/fingers behind the hand/finger barriers (of the meter and the test
leads) that indicate the limits of safe access of the hand-held part during measurement.
Inspect test leads, connectors, and probes for damaged insulation or exposed metal
before using the instrument. If any defects are found, replace them immediately.
This Clamp-on meter is designed to apply around or remove from uninsulated
hazardous live conductors. But still, individual protective equipment must be used if
hazardous live parts in the installation where measurement is to be carried out could be
accessible.
CAUTION
Disconnect the test leads from the test points before changing meter functions.
INTERNATIONAL ELECTRICAL SYMBOLS
!Caution ! Refer to the explanation in this Manual
Caution ! Risk of electric shock
Earth (Ground)
Double Insulation or Reinforced insulation
Fuse
AC--Alternating Current
DC--Direct Current
Application around and removal from hazardous live conductors is permitted
2) CENELEC Directives
The instruments conform to CENELEC Low-voltage directive 2006/95/EC and
Electromagnetic compatibility directive 2004/108/EC

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3) PRODUCT DESCRIPTION
Note: Top of the line model is used as representative for illustration purposes. Please
refer to your respective model for function availability.
1) Transformer Clamp Jaws for AC
current magnetic field pick up
2) Jaw marking lines for ACA (& thus
Power) position error indication
3) Hand/Finger Barrier to indicate the
limits of safe access to the jaws during
current measurements
4) Push-buttons for special functions &
features
5) Input Jack for all functions EXCEPT
non-invasive ACA current (& thus
Power) function
6) Common (Ground reference) Input
Jack for all functions EXCEPT
non-invasive ACA current (& thus
Power) function
7) Slide-switch Selector to turn the
power ON/OFF and Select a function
8) LCD display
9) Jaw trigger for opening the
transformer clamp jaws
10) Jaw center Indicators, at where
best ACA (& thus Power) accuracy is
specified

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4) OPERATION
CAUTION
Before and after hazardous voltage measurements, test the voltage function on a
known source such as line voltage to determine proper meter functioning.
AutoVATM function
Set the slide-switch function-selector to the position.
With no input, the meter displays “ ” when it is ready.
With no ACA current input via the jaws but a voltage signal above the nominal
threshold of DC 2.4V or AC 30V (40Hz ~ 500Hz) up to the rated 600V is present on
V-COM terminals, the meter displays the voltage value in appropriate DC or AC,
whichever larger in peak magnitude. Annunciators “Auto” “dc” and “Auto” “ ” turn
on respectively.
On the contrary, with no voltage signal present on V-COM terminals but a ACA
current signal above the nominal threshold of AC 1A (40Hz ~ 500Hz) up to the rated
1000A is input via the jaws, the meter displays the ACA current value. Annunciators
“” and “Auto” turn on accordingly.
The Auto-VA feature stays at the auto-selected function as long as its signal remains
above the specified threshold. Press SELECT button momentarily to manually select
and lock (annunciator “Auto” turns off) thru the functions ACA, ACV, DCV and then
goes back to Auto-VA.

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CAUTION (Application and removal of the Clamp-on meter)
For non-invasive ACA current measurements, press the jaw trigger and clamp the
jaws around only one single conductor of a circuit for load current measurement. Make
sure the jaws are completely closed, or else it will introduce measurement errors.
Enclosing more than one conductor of a circuit will result in differential current (like
identifying leakage current) measurement. Locate the conductor(s) at the Jaws center
as much as possible to get the best measuring accuracy. For removal, press the jaw
trigger and remove the jaws from the conductor(s).
Adjacent current-carrying devices such as transformers, motors and conductor wires
will affect measurement accuracy. Keep the jaws away from them as much as possible
to minimize influence.
THD%-F Total Harmonic Distortion - Fundamental function (model 157 only)
Total Harmonic Distortion - Fundamental (THD%-F) function is designed to give basic
indication on the presence of Harmonics. It is the percentage ratio of the Total
Harmonics RMS value to the Fundamental RMS value of a voltage or current signal,
and is given by the expression:
THD%-F = (Total Harmonics RMS / Fundamental RMS) x 100%
An ideal sinusoidal waveform has a theoretical value of 0 THD%. A badly distorted
sinusoidal waveform may have a much higher THD% value of even up to several
hundreds. It is thus a good parameter to identify the degree of “cleanness” on power
systems.
When the meter is in ACV or ACA function, THD%-F values will be displayed in the
secondary mini display automatically. Press THD%-F button momentarily toggles
THD% readings to main display.

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Peak-rms mode
Peak-rms compares and displays the maximum RMS value of surge voltage or
current with durations as short as 65ms. When ACV or ACA function is auto-selected
or manual-selected, press and hold Peak-rms button for one second or more
toggles to this mode. The annunciators “P-” “Max” turn on. APO (Auto Power Off)
feature is disabled automatically accordingly.
In ACA function, the Peak-rms mode starts at the highest 1000A (600A for model 357)
range to maximize measuring dynamic range. Before making measurement, press the
Peak-rms button momentarily again can manually select thru lower measuring
dynamic range 400.0A or 40.00A for higher measuring resolutions.
Line-level Frequency (Hz) function
When ACV or ACA function is auto-selected or manual-selected, press Hz button
momentarily toggles to Line-level Frequency (Hz) function. The Hz trigger level is
determined by the selected function-range from where the Hz function is activated.
In ACA function, activating the Hz function during significant measurements can get the
most appropriate trigger level to avoid electrical noises in most cases. Activating the Hz
function at AC 40.00A range (before making significant measurements) can get the
lowest trigger level (highest sensitivity).

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HOLD mode
When any function is auto-selected or manual-selected, press HOLD button
momentarily toggles to Hold mode. The annunciator “ ” turns on. Hold mode freezes
the display for later viewing.
Notes on Displacement Power Factor & Total Power Factor
Introduction: Power is the rate of change of energy with respect to time (in terms of
voltage V and current A). Instantaneous (real) power w=vi where vis the
instantaneous voltage and ithe instantaneous current. The average (real) power is the
mean of vi and is given by:
W = /2vi dt , over the interval from 0 to 2/
Displacement Power Factor (more traditional): Assuming V and A are pure
sinusoidal waveforms without harmonics (as in most traditional cases), that is, v=V
sint and i=Isin (t -), the expression can be simplified to:
W = 1/2 x VxIx Coswhere Vand Iare the peak values, is the
displacement power factor angle, and Cosis the displacement power factor. Using
RMS values, it is written as:
W = Vrms x Arms x Cos
Practically, in such cases without harmonics, is also called the phase-shift angle of
the current A to the voltage V. An inductive circuit is said to have a lagging power factor
since current A lags voltage V (phase-shift angle and thus Sinare both “+”),
and a capacitive circuit is said to have a leading power factor since current A leads
voltage V (phase-shift angle and thus Sinare both “-”).
Total Power Factor (encountering harmonics): When encountering distorted
waveforms with the presence of harmonics, however, the simplified power expression
should not be used since substituting the above mentioned pure sinusoidal V and A
functions cannot fulfill the actual conditions. Cosine of phase-shift angle (Cos  ), or
the displacement power factor, is no longer the only component constituting the overall
power factor. Harmonics do increase apparent power and thus decrease the overall
power factor. That is, the Total Power Factor is actually affected by both phase-shift
angle and harmonics, and is given by the expression:
Total Power Factor (PF) = Real Power (W) / Apparent Power (VA)
In order to improve overall system power factor, nowadays power-system engineer
needs to address both phase-shift and harmonics problems. Practically, harmonics
should be dealt with (e.g. filtering out) before phase-shift to be corrected (e.g. installing
capacitors in parallel with inductive loads).

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Single-Phase Power & 3-Phase Balanced-Load Power functions
Set the slide-switch function-selector to the “3~Bal  1~” Power position.
Default at last selected function.
Press “3~Bal  1~” button momentarily to toggle between “Single-Phase” and
“3-Phase Balanced Load” Power functions. Annunciators “ ” and “3~” turn on
respectively.
Press SELECT button momentarily selects between W(real power), VAR (reactive
power), VA (apparent power) & kWHr (real-time readings or stored result) functions. In
W(real power), VAR (reactive power), or VA (apparent power) function:

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1. PF (Total Power Factor) is displayed automatically in the secondary mini display.
2. Annunciator “A-lags-V” turns on to indicate an inductive circuit is being measured.
That is, the Current waveform is lagging the Voltage waveform, and the phase-shift
angle is “+”.
3. On the contrary, together with significant PF values, WITHOUT “A-lags-V” being
turned on indicates that a capacitive circuit is being measured. That is, the Current
waveform is leading the Voltage waveform, and the phase-shift angle is “-”.
Note:
1. Under proper measurement setups for load circuits, the W(real power) readings are
always positive. Negative Wreadings indicate reversed clamp-on jaws direction or test
leads polarities, or even incorrect voltage lines are being measured as in 3-phase
measurement setups. Correct them for proper “A-lags-V” indications.
2. When encountering largely distorted waveforms, “A-lags-V” detection might be
affected due to the influence of harmonics. It is recommended to manage (e.g. filter
out) harmonics problems before measuring/dealing with phase-shift problems.