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Universal Measuring Device UMG 500A
Installation
When installing and mounting the Universal Measuring Device UMG 500A, the VDE Regulation 0113 must be adhered
to. Before connecting up, ensure that the local supply conditions agree with the data given on the nameplate.
The installation facilities must provide a switch or a power switch. The switch must be installed close to the device, 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.
The currents to be measured must be connected in a like manner to the terminals 1k to 3l. Please note that 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
A switch, key switch or similar can be connected to terminals 11 and 12. When the switch is closed, the instrument cannot
be operated from the keypad, and the LED “remote” at the front of the panel lights up. Unauthorised or inadvertent
operation can thus be prevented. The contact has no influence on the choice of the measurement function or on the storage
of peak values.
“RS 485” Serial interface
Terminals TxD A,B and RxD A,B
These terminals are required in conjunction with the PC software option for communicating with the computer used. (see
serial interface)
