janitza UMG 500 A User manual

Universal Measuring Device
UMG 500 A
Janitza electronic GmbH
Vor dem Polstück 1
D-35633 Lahnau
Tel. [phone]
Fax [phone]
Doc No. 1.010.006.1

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Universal Measuring Device UMG 500A
Content
Application 3
Construction features 3
Functional description 3
Installation 4
Auxiliary voltage 4
Measurement inputs 4
Relay outputs K1 and K2 4
Analogue output “0..20 mA” 4
“Clear work” input 4
“Remote” input 4
“RS 485” Serial interface 4
Commissioning 5
Functional plan 6
Factory presettings 7
Special versions 7
Maintenance note 7
Key functions and Programming 8
“+” key 8
“-” key 8
Primary current of current transformer 8
Voltage transformer 8
Selection of outer conductor L1, L2 or L3 8
Selection key “sum” 8
Voltage 9
Current 9
Mean Current 9
Apparent power 9
Real power 9
Mean real power 9
Measuring period 9
Remaining time 9
Reactive power 10
Real work 10
Reactive work 10
Frequency 10
Power factor 10
Harmonic wave content of voltage 10
Analogue output 11
Work pulses 11
Peak values 12
Date and time 12
Threshold contacts 12
Device Address 12
Software release 12
Serial interface 13
Connection PC to interface converter 13
Communication parameters 13
Bus connection 13
Setting the device address 14
Communication protocol 14
Technical data 15
Dimensions 15
Connection example (3-wire, Aron-connection) 16
Connection example (4-wire) 17
Connection example (Aron-connection) 18
Edition notes
Date refers to page(s) no.:
05.07.94 First edition
01.11.94 Second edition
09.06.95 All pages affected
08.10.96 Application as prescribed, Installation,
Current mean value

Page 3
Universal Measuring Device UMG 500A
Universal Measuring Device UMG 500A is suited for
fixedfrontpanelmountingandtomeaurevoltage,current,
power etc. in low voltage distributions. Current measure-
ment is performed via external current transformers with
5 A secondary (1 A optional). Voltage within the given
measuring range can be connected directly to the device.
Compared with individual analogue measuring instru-
ments,the UniversalMeasuring Devicehas theadvantage
of requiring considerably less mechanical content and
wiring content. Stocking is easier, because with the
Universal Measuring Device UMG 500A, practically all
standard measurement ranges in low voltage installations
can be achieved.
Applications include:
- monitoring and control of electrical parameters
in energy distribution systems
- sensor in building wiring systems
The following measured values can be called up:
• voltage
• current
• mean current
• apparent power
• real power
• mean real power
• reactive power
• frequency of voltage
• harmonic wave content of voltage
• power factor
• peak values with date and time *1)
• real work
• reactive work
Outputs:
• analogue output
• threshold contacts
• serial interface (designed for networking)
Application
*1) Peak values of harmonics are stored without date and
time.
Construction features
Universal Measuring Device UMG 500A is housed in a
144 mm x 144 mm plastic case suitable for front panels
mounting.
Operationandprogrammingare achievedviaamembrane
keyboard and four-digit display with 20 mm characters.
The auxiliary voltage, measurement inputs etc. are con-
nected at the rear panel via protective plug terminals.
Functional description
The three phase electronic measuring system measures
anddigitizestheeffectivevalueofvoltagesandcurrentsin
a 50 Hz or 60 Hz power supply. Every 2 seconds, a
sampling measurement is carried out. By means of these
measurements, the built-in microprocessor computes the
electrical values. The desired values can be displayed on
keystroke, thedimensionsofthevaluesbeingindicatedby
the relevant LED.
Peakvaluesand programming data arestored in a battery-
supplied memory.
Warning note
In case of three-wire connection, the measuring
partisconfiguredasan“Aron”-connection.Dueto
this, current in L2 will be ignored for power meas-
urement.
For this reason, the results of the following func-
tions:
P, Q, S, power factor, W, and B
are valid only as the sum. The real power is calcu-
lated as follows:
PΣ= P1 + P3

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Universal Measuring Device UMG 500A
Installation
Wheninstallingand mountingtheUniversal MeasuringDeviceUMG 500A,theVDE Regulation0113must beadhered
to. Before connecting up, ensure that the local supply conditions agree with the data given on the nameplate.
Theinstallation facilitiesmustprovide aswitch orapower switch.The switchmustbe installedclose tothedevice, easy
to be operated by the user. The switch must be marked as a disconnection device for the UMG 500A.
Auxiliary voltage
Terminals L, N
For auxiliary voltage see nameplate. The auxiliary voltage must be connected via a 2A time-lag auxiliary fuse to the
terminals “auxiliary voltage” L and N at the rear of the instrument.
Measurement inputs
Terminals L1, L2, L3, 1k-3l
The voltages to be measured, L1, L2 and L3 must be similarly connected via a 2A auxiliary fuse to the terminals L1, L2
and L3.
Thecurrents to bemeasured mustbeconnected ina like mannerto the terminals1k to3l.Please notethat the continuous
measurement current must not exceed 5A, (1 A for instruments with .../1 A transformers), whether measuring directly
or via a current transformer.
Relay outputs K1 and K2
Terminals 1-3, 4-6
The instrument is equipped with two floating threshold value contacts “min” and “max” which are available as change-
over contacts with terminals 1 to 3 or 4 to 6. If the reading falls below the “min” value programmed for the threshold
function or rises above the “max” value, the appropriate relay is activated. The threshold values “min” and “max” can
be programmed via keystrokes.
Analogue output “0..20 mA”
Terminals 7, 8
The measured values displayed are converted by the UMG into a 0..20 mA analogue signal. The analogue signal can
be tapped at terminals 7 and 8 and passed on, for example, to a recorder. It is possible to connect several instruments
in series, but the total load may not exceed 500 Ω. The analogue output is scaled with the help of key “0..20 mA”.
Optionally, the device can be provided with 4..20 mA analogue output.
“Clear work” input
Terminals 9, 10
A contact can be connected to terminals 9 and 10 which when closed, erases the real work and reactive work which has
been registered up to this point and restarts the time measurement. Measurement of real and reactive work then
recommences synchronously with the value 0 kWh or 0 kvarh.
“Remote” input
Terminals 11, 12
Aswitch,keyswitchorsimilarcanbeconnectedtoterminals11and12.Whentheswitchisclosed,theinstrumentcannot
be operated from the keypad, and the LED “remote” at the front of the panel lights up. Unauthorised or inadvertent
operationcanthusbeprevented. Thecontacthasnoinfluenceonthechoiceofthemeasurementfunctionoronthestorage
of peak values.
“RS 485” Serial interface
Terminals TxD A,B and RxD A,B
TheseterminalsarerequiredinconjunctionwiththePCsoftwareoptionforcommunicatingwiththecomputerused.(see
serial interface)

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Universal Measuring Device UMG 500A
Commissioning
1. Connect auxiliary voltage.
The 7-segment display shows “0”, or if a measured voltage is already present, another reading.
2. Programming
When the auxiliary voltage is present, the device is ready for use and can be programmed.
To do this, the “local/remote” contact must be open (the LED must not light up).
2.1 Programme the current transformer.
2.2 Programme the voltage transformer.
2.3 If required, programme the analogue output.
2.4 If required, programme the relay outputs
2.5 If required, alter the device address.
Four-wire measurement
3. Measured voltage
3.1 Switch off voltage to UMG 500A and connect voltage path L1 - N.
3.1.1 Switch on auxiliary voltage and measured voltage.
3.1.2 Using the operating keys of the UMG 500A, cause the voltage in L1 to be displayed and compare it with the
voltage applied at L1 - N.
3.2 Repeat the steps under 3.1 for the voltage paths L2 and L3.
Warning!Becausethe frequency ismeasuredin L1, voltage mustbe present at thisterminal.If not, thedeviceassumes
that the frequency is 50 Hz, which results in measuring errors.
4. Measured current
4.1 Switch off voltage to UMG 500A and connect current path for L1.
4.1.1 Switch on auxiliary voltage, measured voltage and measured current.
4.1.2 Using the operating keys of the UMG 500A, cause the current in L1 to be displayed and compare it with the
current applied at “k-l”.
4.1.3 Using the operating keys of the UMG 500A, cause the real power in L1 to be displayed.
If the display shows a “-” it indicates that generating mode is present or that “k” and “l” have been transposed.
4.2 Repeat the steps under 4.1 for the current paths L2 and L3.
Three-wire measurement
3. Measured voltage
3.1 Switch off voltage to UMG 500A and connect voltages L1, L2 and L3.
3.1.1 Switch on auxiliary voltage and measured voltage.
3.1.2 Using the operating keys of the UMG 500A, cause the voltages to be displayed and compare it with the
voltages applied.
3.1.3 Check rotary field.
4. Measured current
4.1 Switch off voltage to UMG 500A and connect current path for L1.
4.1.1 Switch on auxiliary voltage, measured voltage and measured current.
4.1.2 Using the operating keys of the UMG 500A, cause the current in L1 to be displayed and compare it with the
current applied at “k-l”.
4.1.3 Using the operating keys of the UMG 500A, cause the real power in L1 to be displayed.
If the display shows a “-” it indicates that generating mode is present or that “k” and “l” have been transposed.
4.2 Repeat the steps under 4.1 for the current paths L2 and L3.

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Universal Measuring Device UMG 500A
"opt.": optional; see Special versions
"sqrt": square root
"Ref.": reference conditions for the accuracy data:
frequency 49.5 .. 50.5Hz or 59.5 .. 60.5Hz
harmonic content <10% of basic wave
ambient temperature +18°C ... +27°C
current and voltage in the range 20% ... 90% of measuring range
cos phi in the range 0.5 ind -1 - 0.5 cap
Functional plan
Mea-
sured
values
Measurement
function
Voltage
UApp. current I Mean current Mean real
power
Real
power P App. power S React. power Q React. work Real work W Fre- quency f power factor
cos phi 5. 7. 11. 13.
Harmonic wave
Measuring method Ueff Ieff 15 min./
99.5% W/ Restzeit measure PS = Ueff* Ieff
Q=
sqrt
(S²-P²)Q*t W=P*t zero
crossing P/S Fourier analysis
Summation 4-wire
measurement - - - P1+P2 +P3 P1+P2 +P3 S1+S2 +S3 Q1+Q2 +Q3 (Q1+Q2 +Q3)*t (P1+P2 +P3)*t -Sum (P)
----------
Sum (S)
----
Summation 3-wire
measurement (option) - - - P1+P3 P1+P3 (S1+S2
+S3)
/sqrt (3) Q1+Q3 (Q1+
Q3)*t (P1+ P3)*t - ----
Dis-
play
func-
tions
Sign ind / cap - - - - - - x/x x/- - - x/x ----
Motor/
gener. - - - x/- x/x - - - x/- -x/x ----
Transient
values
L1 0 .. 9999
V / opt.:
0.00 ..
99.99 kV
0 .. 5500
A0 .. 5500 A
-
0 .. 9999
kW / opt.:
0.00 ..
99.99
MW
0 .. 9999
kVA /
opt.: 0.00
.. 99.99
MVA
0 .. 9999
kvar
0.000 ..
9999
kvarh
(*255)
0.000 ..
9999
kWh
(*255)
48.00 ..
62.00Hz
100
0.0 .. 25.5%
L2 --
L3 --
Sum - - - 0 .. 9999
kW - ----
Peak values
L1
0 .. 9999
V / opt.:
0.00 ..
99.99 kV
0 .. 5500
A0 .. 5500 A
-- - 48.00 ..
62.00Hz
0.0 .. 25.5%L2 -- - -
L3 -- - -
Sum - - - 0 .. 9999
kW - - - - - - -
Date/
Time x x x x x x x - - x x - - - -
Accuracy referred to full scale
value
+/- 2
digit +/- 2 digit +/- 2 digit +/- 5 digit +/- 5 digit +/- 5 digit +/- 5 digit +/- 5 digit +/- 5 digit +/- 2 digit +/- 2 digit +/- 10 digit
+/- 0.5 % +/- 0.5 % +/- 0.5 % +/- 1.5 % +/- 1.0 % +/- 1.0 % +/- 1.5 % +/- 1.5 % +/- 1.0 % +/- 0,5 % +/- 1.0 % +/- 10 %
Scaling of analogue output
0..20 mA / optionally 4..20 mA
(resolution 8 bit)
0 .. 9999
V / opt.:
0.00 ..
99.99 kV
0 .. 9999
A0 .. 9999 A0 .. 9999 kW
0 .. 9999
kW / opt.:
0.00 ..
99.99
MW
0 .. 9999
kVA /
opt.: 0.00
.. 99.99
MVA
9999 ind.
.. 0 ..
9999
cap.
0=10mA
0..9999
varh /
pulse
(see
"scaling
of ana-
logue
output")
0 .. 9999
Wh /
pulse
(see
"scaling
of ana-
logue
output")
Variation
from
50/60 Hz
in 0.01
Hz steps
50/60 Hz
=10 mA
Variation
from 1.00
in 0.01
steps
1=10mA
0 .. 25%
Setting range of threshold
contacts
0 .. 9999
V / opt.:
0.00 ..
99.99 kV
0 .. 9999
A0 .. 9999 A0 .. 9999 kW
0 .. 9999
kW / opt.:
0.00 ..
99.99
MW
0 .. 9999
kVA /
opt.: 0.00
.. 99.99
MVA
9999 ind
.. 0 ..
9999cap
0..9999
kvarh
(without
over-
flows)
0 .. 9999
kWh
(without
over-
flows)
00.00 ..
99.00Hz
0.00ind
... 1.00
...
0.00capp
0 .. 25%
rem.time

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Universal Measuring Device UMG 500A
Factory presettings
•Current transformer: 5000A/5A
•Voltage transformer factor 1.0
•Measuring function voltage
•Measurement phase L1
•Device address (RS485) 1
•Measuring period for real power mean value 900 seconds
•Analogue output
Function current
Phase L1
Scaling 20 mA = 2000 A
•Relay output
Function current
Phase L1
K1 (min.) switching threshold 0 A
K2 (max.) switching threshold 9999 A
•Date and time actual time (without automatic changing summer /winter)
Maintenance note
The built-in batteries must be changed by trained staff after a period of about 5 years. The batteries have a design life
of approx. 8 to 10 years.
Batteries: 2 off Lithium batteries, voltage 3 V, diameter 12.5 mm, 2.5 mm thick, Panasonic, order code BR-1225
Special versions
The following special versions are available: Standard Option
•Current transformer inputs 5 A 1 A
•Voltage display 9999 V “kV”+“3-wire”: up to99.99 kV
“kV”: up to 30.00 kV
•Real and apparent power display 9999 kW/kVA/kWh 99.99 MW/MVA/MWh
•Analogue output 0 .. 20 mA 4 .. 20 mA
•Wiring of voltage measurement inputs 4-wire 3-wire
Power measurement in “Aron”
connection and display of
current in L2.
If used in conjunction with an external adapter transformer the device is also suitable for the following voltages:
•525, 600 and 1000 V

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Universal Measuring Device UMG 500A
Primary current of current transformer
When this key is pressed, the programmed state is displayed and can be altered by additionally pressing the
“+”or “-”keys. Setting range: 1 ... 5000 A in 1 A steps.
The set value is always based on a current transformer secondary current of 5 A (standard).
Example: for a current transformer of 500/5, “500”must be set.
Forinstruments fittedwith a 1A transformersecondary (optional),the primarycurrentmust beset similarly
Example: for 1000/1 the value is “1000”.
.. / 5A
-
+
Key functions and Programming
Programming of Universal Measuring Device UMG 500A is carried out with the remote/local contact open, using the
keyboard and the digital display. Following a power failure, it is not necessary to reprogram the device, because the
programmed data and peak values are stored.
“+”key
This key is used - partly in conjunction with other keys - for the following functions:
•Changing set values
•Reading the peak value of the displayed function.
•Indicating overflows of work measurements (W)
“-”key
This key is used - partly in conjunction with other keys - for the following functions:
•Changing set values
•Erasing the peak value of the displayed measurement function.
•Erasing the accumulated work
•Restart of averaging power and current
Summe
ΣΣ
ΣΣ
Σ
sum
Selection key “sum”
Withthiskey,thesumsofthemeasurementfunctionsrealpower,apparentpower, reactivepower,realwork,
reactivework and powerfactor, from L1,L2 and L3are displayed. Forall measurement functionsother than
those referred to, this key is inoperative.
L2
L3
L1
Selection of outer conductor L1, L2 or L3
The outer conductor, for which the associated measurement values are to be displayed, is selected with this
key. The selected outer conductor is indicated by the LED “L1”, “L2”or “L3”. The frequency is only
measured in L1.
U
Voltage transformer
Ifrequired,the ratioofthevoltagetransformer usedcanbe setwiththe aidofthiskey. Thefactor
isdisplayedwithone decimalplace. Incombinationwiththe“+”or“-”keys,thedisplayed value
can be altered. Setting range: 0.1 ... 999.9
Example: Transformer Displayed / set value
10,000 V/100 V 100.0
12,000 V/110 V 109.1
.. / 5A
Note
The voltage transformer ratio is set to 1.0 for the standard version. If this value is wrongly set
by mistake, this will result in the measured voltage and the values derived from it being
incorrectly calculated and displayed!
Note
Incaseofoption../1A,primarycurrentmaynotbesethigherthan1000A,otherwisecalculation
of current and other dependent values (power, power factor, work) will be incorrect!

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Universal Measuring Device UMG 500A
I
.. / 5A
Remaining time
By means of these keys, the remaining time in the present measuring period will be displayed in
seconds. After a measuring period has been elapsed, i.e. the remaining time has reached zero, a
new measuring period starts with the set value. By erasing the real work, the measuring period will also be
restarted.
%
.. / 5A
Measuring period
The measuring period to calculate mean real power can be read out by means of these keys. In
addition with the “+”and “-”key, the value can be set in steps of 1 second.
Setting range: 60 ... 9999 seconds.
Pmin
Mean real power
Byholdingdown the “P”key and operating the“min”key,the mean real power isdisplayed. To
differentiate this function from the display of the present value of real power, a decimal point
appearsonthe rightofthequantity.Theinstrumentaccumulates workonlyby theconsumedrealpower.The
mean value calculates mean power as follows:
Mean real power = accumulated work in present measuring period / remaining time of meas. period
Real power
Thisfunction displaysthe real powerin theouter conductors orthesum ofall threereal powersisdisplayed.
The unit of measurement “kW”is indicated by an LED. With generator operation (power supply service),
therealpowerisdisplayedwiththreedigitsas“-###”. Asanoption,theinstrumentcandisplaytherealpower
in MW to two decimal places.
P
UI
Apparent power
Thisfunctionshowstheapparent powerofthe measureditems. Theunit iskVA;inthisinstance
it is indicated by the LEDs “V”and “A”. As an option, the instrument can display the apparent
power in MVA to two decimal places.
Imin
Mean Current
Byholdingdownthe“I”keyandoperatingthe“min”key,themeancurrentisdisplayed.Toselect
ameasuringphaseodertoerasethemaximumvaluekey“I”mustbekeptpressed.Todifferentiate
this function from the display of the present value of current, a decimal point appears on the right of the
quantity.
This function shows the mean value of the current over a period of 15 minutes. With the method for
generating the mean value used here, the mean value over the given time approaches to within 99.5% of the
present value.
U
Voltage
Whenthiskey is pressed, the devicedisplaysthe effective value of the voltagetoneutral or to the nextphase
(L1-L2;L2-L3;L3-L1). The unit is indicated by the LED“V”.Instruments with the option “kV”display the
measurementvalueintheformat##.##kV.Instrumentswiththeoption“3-wire”onlydisplayvoltageagainst
next phase.
Display range: 1 ... 9999 V (standard)
0.01 ... 30.00 kV (option “kV”)
0.01 ... 99.99 kV (option “kV”+ option “3-wire”)
I
Current
This function displays the effective value of the current in the selected current path. The LED “A”indicates
the unit of measurement.

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Universal Measuring Device UMG 500A
W
f
cos ϕϕ
ϕϕ
ϕ
Harm.
%
Q
W
Reactive power
This function displays the reactive power in the outer conductors or the sum of their reactive powers. The
unit “kvar”is indicated by an LED. The direction of the phase displacement between voltage and current is
indicated by the LEDs “ind”or “cap”.
Real work
After this key has been pressed, the device displays continuously the sum of the real work extracted in the
selectedouter conductoror thetotal realwork. With generatoroperation,real powerreturned tothe supplier
is not subtracted. The unit is indicated by the LED “kWh”.
The display range is 1 to 9999 kWh. If the full scale value is exceeded, the display restarts at 0 kWh and the
numberof overflows canberead off bypressing the “+”key. Inthis case, thework is givenbythe following
expression:
number of overflows * 10000 kWh + displayed value
In addition, the device counts the time from the start of measuring work. It can be read off by using the
following key combinations:
1.) Press and keep pressed down 2.) Additionally operate Display
ΣΣ
ΣΣ
Σdays (max. 9999)
L3 hours
L2 minutes
L1 seconds
The value of the work and the elapsed time are erased if the contact “clear work”at the rear of the device is
closed or if key “W”is kept pressed down and the “-”key pressed simultaneously. Measurement of work
startsafreshimmediately after erasure. If there isapower failure, the time measurement willbeinterrupted.
Frequency
This function displays the frequency of the voltage in L1. The unit of measurement is indicated by the LED
“Hz”.
Power factor
This key is used to display the power factor cos phi in L1, L2 or L3 or to measure the total power factor. The
LED“cos ϕ”indicatestheoperation ofthis function. Thedirection ofphasedisplacement isindicated by the
LEDs “ind”or “cap”. With generator operation (power supply service), the power factor is displayed as “-
#.##”.
Harmonic wave content of voltage
Thisfunctiondisplays the harmonic wavecontentof the measured voltage. TheLED “%”indicates the unit.
The percentage shown is based on a voltage of 230 V. At the left hand side of the display an ordinal number
appearswhichshows which harmonic iscurrentlybeing displayed ( 5th,7th,11th, A=13th). The percentage
value is displayed in the two right-hand segments. With each successive use of the “Harm”key, the value
of the next harmonic wave is shown.
W Q
Reactive work
By keeping key “W”pressed down and simultaneously pressing key “Q”, reactive work is
displayed. LEDs “kWh”and “Q”light up. The information given under measurement function
real work applies in a similar way for this measurement function.
Attention:
•Only inductive power will be registered.
•The registered duration of the work measurement is valid for both real and reactive work.
•Iftheworkiserased,eitherviacontact“clearwork”orviathekeycombinationgivenintheprevioussection,
not only real work but also reactive work are erased.

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Universal Measuring Device UMG 500A
Iw >= P
Calculation of the pulse valence:
Iw: Pulsevalence
[Wh/pulse] P: Maximum
expected real power [kW]
Work pulses
Output of real or reactive work presents a special case. In this case, a proportional analogue signal is not
provided,butpulses,whosefrequencyisproportionaltotherealorreactivepower. Theanalogueoutputthus
behaveslikeameteringpulsesender. ThepulsevalenceissetviascalingoftheanalogueoutputinWh(varh)/
pulse. This can be selected between 1 and 9999 in steps of 1 Wh (varh)/pulse.
Themaximumpulse frequency of the analogueoutputis 0.25 Hz, i.e. onepulsein four seconds. If thepower
exceeds the maximum pulse frequency, the surplus of pulses are stored and will be transmitted later, if
possible. In this case, the momentary pulse duration does not represent the momentary power.
Example 1:
The maximum pulse valence is to be calculated for a
three-phase network for which P = 500 kW.
Iw >= P
Iw >= 500 kW
Thisindicates that thepulsevalence must beset equal
toorbiggerthan500,ifthemaximumpulsefrequency
of 0.25 Hz should not be exceeded.
0..20mA
Analogue output
Allocation
In order to allocate a particular measuring function to the output, the desired measuring function
and the measurement phase must first be selected. After this, the function set is allocated to the
analogue output by operating the keys illustrated on the left.
Scaling
The analogue output can be scaled for any quantity to be measured, independently of the choice of display
function. The object of this scaling is to make maximum use of the range 0 (4) to 20 mA in order to achieve
the largest possible resolution of the measured value, without going outside the scale. The setting range of
thescalevalue depends on the function selected, and canthereforevary from function to function. (see table
Functional plan.
The data in brackets applies to devices fitted with a 4 .. 20 mA analogue output.
Attention: If real power is assigned to a 4 .. 20 mA analogue output, the output current will decrease below
4 mA in case of generating mode.
.. / 5A
Example 2:
A pulse receiver can only evaluate a pulse valence
of maximum 1500 Wh/pulse.
Iw >= P
1500 >= P
The maximum power which can be evaluated is
1500 kW.
0..20mA

Page 12
Universal Measuring Device UMG 500A
I
Peak values
Universal measuring device UMG 500A stores the peak value and the date and time of registering for most of the
measuringfunctions. Thereisnostorage ofpeak valuesforrealworkand reactivework. In thecaseofharmonicwaves,
the peak values are stored without date and time. In the case of measurement function reactive power and cos ϕ, the
highest inductive value is stored.
Todisplaythepeakvalue,therespectivemeasurementfunctionmustbeselected.Thepeakvalueisdisplayedbypressing
the “+”key.
The peak value can be erased by pressing the appropriate function key (e.g. “P”for real power) and keeping it pressed
and additionally pressing the “-”key.
The date and time of the respective peak value can be called up by operating the following keys (in this example, date
and time are displayed for the peak value of current):
1.) Press and keep pressed down 2.) Additionally operate Display
max year
ΣΣ
ΣΣ
Σdays
L3 hours
L2 minutes
L1 seconds
f
.. / 5A
Software release
By pressing the two keys simultaneously, the number of the software version fitted in the
instrument can be displayed, e.g. “1.00”.
Date and time
The actual date or actual time can be displayed by using the procedure described under Peak values, but using key “../
5A”instead of the function key for the corresponding measurement value. In combination with the keys “+”and “-”,
the settings can be changed. There is no automatic changeover for summer time and winter time.
.. / 5A
1.) Press and keep pressed down 2.)Additionally operate Display
max year
ΣΣ
ΣΣ
Σdays
L3 hours
L2 minutes
L1 seconds
Threshold contacts
The functions “min”and “max”can be used to monitor a quantity to be measured. If the threshold contacts are used to
monitor real or reactive work, only the places in front of the decimal point of the measured value and the overflows are
takenintoaccount. Ifthethresholdcontactsareusedtomonitor meanrealpower, therelayswill switchonlyafterafixed
delay time of 30 seconds, which starts simultaneously with a new measuring period.
max
min
min max
Allocation
Inordertoallocatethethresholdfunctiontoaparticularmeasurementfunction,themeasurement
function and the measurement phase must first be selected. Following this, the function which
has been set is allocated to the threshold function by simultaneous operation of the keys shown on the left.
Programming
With the aid of these keys, the value can be set, which if exceeded or underscored, causes the corresponding
relay to operate.
W
.. / 5A
Device Address
The device address, which can be set by means of DIP- switches at the left hand side panel, can
be displayed by pressing these keys.

Page 13
Universal Measuring Device UMG 500A
PC or similar
with RS-232-
Interface



○○○
RS485
RS232
(V24)
Interface
converter
UMG
Station 1 UMG Station n
UMG
Station 3
UMG
Station 2
Serial interface
Universal Measuring Device UMG 500A is fitted with an
RS-485 serial interface. This enables up to 32 Universal
Measuring Devices to be driven on a common bus with a
total length of up to 1000 m. With the aid of a communi-
cationsprotocol, measurement data canbe read from each
connectedUMGandsettingdata(e.g.currenttransformer)
can be transmitted to each UMG.
Figure: Connection example for serial interface
Connection PC to interface converter
The interface converter can be plugged in directly to the
COM port of a PC (25-pin plug) via the adapter provided
(socket-socket).
Great care must be taken to ensure that the
parallel port of the PC (25-pin socket) is not
used, because otherwise damage to the device
can occur.
Alternatively, a connecting cable (25-pin, socket-socket)
can be used instead of the adapter. This cable must not be
longer than 5 m.
The RJ-11 socket of the interface remains unused.
Communication parameters
The following transmission parameters are permanently
set on the UMG 500A:
baud rate 9600 bd
data bits 8
parity N
stop bits 1
These parameters must also be set at the PC, e.g. using the
DOS command:
mode com1:9600,n,8,1
Bus connection
All measuring stations (UMG 500 A) are connected with
oneanotherviaafour-core screenedcableand tothe 4-pin
terminal strip of the interface converter, whereby the
screeningisnotconnected. Thepinassignmentisgivenin
the following plan:
UMG(s) Converter
Recommended cable type: JY(St)Y 2 x 2 x 0.6 or similar.
Maximum cable length: 1000 m.
16
15
14
13
1
2
3
4
RxD A
RxD B
TxD A
TxD B

Page 14
Universal Measuring Device UMG 500A
→→
→→
→ON Value
S8 128
S7 64
S6 32
S5 16
S4 8
S3 4
S2 2
S1 1
S4 = ON 8
+
S1 = ON 1
=
Address 9
Setting the device address
The device address is set via an 8-fold DIP switch, which
can be reached through a cutaway on the left hand side of
the device. Addresses from 0 to 255 can be set.
The switches are marked with the numbers 1 to 8. An
arrow symbol, marked with ON, indicates the position of
the switch.
TheseswitchesS1toS8arecodedintheDUALSYSTEM,
i.e. each switch has double the value of the previous one
(1-2-4-16-32-64 etc.).
Figure: Example shows address 9
The position of the switches can be changed as required
using a ballpoint pen or narrow tweezers.
Do not use a pencil for this adjustment, because the lead
can break off and cause a short circuit.
Communication protocol
The communication protocol enables communication to
take place between the host system (the PC) and the
measuring stations using the master-slave principle, i.e.
themeasuring stationsnevertransmitindependently,only
after being called up by the host system. The protocol
consists essentially of control characters for beginning
and end of protocol, the device address of the selected
measuringstation,startaddressandcontentofdesireddata
and an end of protocol or acknowledge character. It does
not use a handshake signal.
AllUMGswhichareconnectedonthebusreceivethedata
transmittedfromthePC. Assoonasthedeviceaddresshas
been transmitted, the relevant device starts to answer the
message in relation to the required operating mode. The
other stations remain passive.
Note: Onlystationswithdifferentdeviceaddressescanbe
driven from a bus.
A message is only evaluated by the UMG after complete
and error-free transmission. The UMG breaks off the
connection if it does not receive further characters after
120 ms.
Dimensions
Device address
Copyright
© Janitza electronic GmbH 1995, 1996
This handbook may not be copied or reproduced by any means in whole or in part without the written permission of
Janitza.
(Dimensions in mm)

Page 15
Universal Measuring Device UMG 500A
Technical data
Auxiliary voltage: see nameplate
Mains frequency: 50 Hz / 60 Hz
Power consumption: approx.. 10 VA
Measuring inputs
Signal frequency: 45 ... 750 Hz
Voltage paths
Power consumption: 2.75 VA at 230 V
Nominal measured voltage
Standard: Un= 230 V (80 ... 250 V)
Optional: Un = 120 V (40 ... 130 V)
Current paths
Power consumption in each current path: 1.25 VA at 5 A
Nominal measured current
Standard: In= 5 A (50 mA ... 5.5 A)
Optional: In = 1 A (10 mA ... 1.1 A)
Continuous rating: 1.2*In
Short-time rating: 2.4*In(continuous: 5s, interruption with max In: 1h)
Analogue output load: max. 500 Ω
Sampling period: 2 seconds, device shows the average value of 5 sam-
ples
Accuracy in relation to full scale value
V, A, Hz ± 0.5%, ±2 digit
kW, kVA, cos phi, kWh ± 1%, ±5 digit
kvar, kvarh ±1.5%, ±5 digit
Harmonic wave content ± 10%, ±10 digit
Environment
Operating temperature: - 10°C ... +45°C
Storage temperature: - 20°C ... +60°C
Humidity class: F to DIN 40040 (15 ... 95 % without condensation)
Operating altitude: 0 ... 2000 m above sea level
Rated impulse voltage: 4 kV
Overvoltage category: III
Test voltage
Measuring inputs vs. aux. voltage: 2.2 kV
Measuring inputs vs. interface: 2.2 kV
Auxiliary voltage vs. interface: 2.2 kV
Protection class: II, protection isolation, without protective ground
Standards considered
EN 61010-1 03.1994 Safety reglementations for electrical measuring,
control, regulation and laboratory instruments
EN 55011 06.1992 RFI product standard
Group1,ClassB(residentialandcommercialpremises)
EN 50082-2 03.1995 EMC basic standard, part 2: industrial premises
Weight: 1,5 kg
Protection class
Front: IP 50
Rear: IP 20
Attachable screw terminals: IP 20
Real time clock: +/- 1 minute / month

Page 16
Universal Measuring Device UMG 500A
Connection example (3-wire, internal Aron-connection)
switch closed: clear work
switch open: measure
serial interface
RS 485
analogue output
floating
threshold
contacts
auxiliary voltage
see nameplate
consumer
measured voltage
see nameplate
interface
converter
RS 485 -
RS 232
switch closed: remote
switch open: local
3l
3k
2l
2k
1l
1k
50 mA .. 5.5
A

Page 17
Universal Measuring Device UMG 500A
Connection example (4-wire)
switch closed: clear work
switch open: measure
serial interface
RS 485
analogue output
floating
threshold
contacts
interface
converter
RS 485 -
RS 232
switch closed: remote
switch open: local
consumer
auxiliary voltage
see nameplate
3l
3k
2l
2k
1l
1k
50 mA .. 5.5
A

Page 18
Universal Measuring Device UMG 500A
Connection example (Aron-connection)
switch closed: clear work
switch open: measure
serial interface
RS 485
analogue output
floating
threshold
contacts
interface
converter
RS 485 -
RS 232
switch closed: remote
switch open: local
auxiliary voltage
see nameplate consumer
measured voltage
see nameplate
60 .. 250 V
3l
3k
2l
2k
1l
1k
50 mA .. 5.5
A

Page 19
Universal Measuring Device UMG 500A
Lahnau, 21.06.1996 Signature
Markus Janitza
EC- Directive: 89/336/EWG (electromagnetic compatibility)
73/23/EWG (low voltage)
Standards considered:
EN 61010-1 03.1994 Safety reglementations for electrical measuring, control,
regulation and laboratory instruments
The device corresponds to protection class II
(without protective ground terminal) and is suited for applications
in overvoltage category III and contamination level 2.
EN 55011 06.1992 RFI product standard
Group 1, Class B (residential and commercial premises)
EN 50082-2 03.1995 EMC basic standard
Part 2: Industrial premises
agrees with the following requirements of the European Community:
herewith confirms that the product
Description: Universal Measuring Device
Type: UMG 500A
Janitza electronic GmbH
Vor dem Polstück 1
D-35633 Lahnau
Tel. [phone]
Fax [phone]
The manufacturer
Declaration of Conformity