User Manual

4/10 © 2005 Siemens Switzerland Ltd. Subject to change
Building Technologies MeterProxy Small Building CM1N5658en
Building Automation 02.12.2005
A web browser (Microsoft Internet Explorer) is used to parameterize the MeterProxy.
Parameterized data is protected against power outages (provided the backup battery is
enabled).
The MeterProxy Small Building firmware can be updated on site. This allows for a
simple process to resolve errors and increase functionality.
MeterProxy Small Building has 5 counter inputs and offers M-bus expansion options
allowing for connection of additional pulse adapters.
The counter inputs are used for acquisition of meter readings. The value-per-pulse and
the offset for each counter input can be set as parameters. The following options are
supported:
• Pulse transmitter with NAMUR interface (DIN 19234).
• S0 interface (DIN43864 / IEC62053-31).
• Reed contacts / semiconductor switches.
Pulse transmitters with NAMUR interfaces are monitored for short circuit and open
circuit. Other types of transmitter (S0, reed contact etc.) do not support this function.
In normal operation, provided that the MeterProxy is connected to the power supply, all
the transmitter types referred to above can be connected and operated in accordance
with the standard.
In battery-backed mode, when there is no supply voltage available to the MeterProxy,
the metering equipment receives its power from the backup battery. This mode of
operation ensures that the acquisition of pulses from the connected meters is
maintained if the power supply to the MeterProxy fails. To ensure that maximum
possible battery backup period, the transmitter voltage is reduced to 3 V and is only
connected while sampling is in progress. For this reason, the following measures are
required to improve immunity to interference:
• Use screened, twisted pair cable.
• Connect one end of the screen to the MeterProxy device (a shield bus must be
provided on site).
• The maximum cable length for the pulse transmitters is 10 m.
• The pulse transmitter must be volt-free.
Remotely installed meters can be connected via a pulse adapter by use of the M-bus.
For this function, the MeterProxy Small Building can be extended with an M-bus
expansion card (ACX51.26) or an external M-bus level converter. At present, only
certain pulse adapters may be connected to the M-bus:
• Siemens Ultraheat AEW21.2.
• Relay PadPulse M1, M2, M4.
• Relay AnDi 4 (to add analog measured variables).
Meters with their own M-bus interface are not supported.
The pulse adapters receive their power via the M-bus. The M-bus card can supply
devices with an overall bus load equivalent to a total of six bus loads. For example, a
relay PadPulse M4 requires 2 bus loads. Thus, max. 3 of this type can be connected.
Information about the load on the bus and the connection of meters to the pulse
adapter can be found in the relevant data sheets or manuals.
Parameterization
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Supported metering
equipment
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