Basic Documentation

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Siemens Modular Heating Controller RMH760B CE1P3133en
Building Technologies 12 Function block meter 2017-09-29
The meters are used to optimize plant operation. They also serve for limiting the
pulses.
The following types of meters can be used:
• Mechanical pulse sources (Reed contact) with no Namur circuitry, having a maximum
pulse frequency of 25 Hz and a minimum pulse duration of 20 ms
• Electronic pulse sources having a maximum pulse frequency of 100 Hz and a
minimum pulse duration of 5 ms
Electronic pulse sources, such as Open Collector outputs, generate shorter, less
bouncing pulses than mechanical pulse sources, such as relays or Reed contacts.
To ensure full flexibility with regard to models, the type of meter can be selected:
Main menu > Commissioning > Settings > … or
Main menu > Settings > Inputs > RMH760.X… (or RMZ78.…)
Operating line
Range
Factory setting
Type Mechanically /
Electronically
Mechanically
A name can be entered for every meter (refer to section 12.8 " Assignment of text"). If,
after assigning a name, the meter is called up, it is no longer "Meter 1" (or 2, 3, or 4)
that appears, but the name entered
• The pulse meters integrated in the RMH760B are not suited for billing purposes, the
reason being insufficient accuracy. To ensure valid billing data, readout must take
place directly on the meters (heat meters, electricity meters, etc.)
• Meters using Namur or S0 circuitry are not supported
• 4 independent meters are available
12.4 Pulse valency
Every pulse delivered by a pulse source corresponds to a certain consumption value.
The pulse valency is imprinted on the meter. It must be entered as a numerator and
denominator.
Settings:
Pulse valency numerator = 20
Pulse valency denominator = 1
Pulse unit = liter
 Pulse valency =
20 liters / pulse
Settings:
Pulse valency numerator = 10
Pulse valency denominator = 3
Pulse unit = Wh
 Pulse valency =
3.33 Wh/pulse
Main menu > Commissioning > Settings > … or
Main menu > Settings > Data acquisition > Meter 1 (or 2, 3 or 4)
Operating line
Range
Factory setting
Pulse unit Wh / kWh / MWh /
kJ / MJ / GJ /
ml / l / m3 /
Heat cost unit /
No unit / BTU
kWh
Pulse valency numerator
1…9999
1
Pulse valency denominator
1…9999
1
Types of meters
Setting
Note on "Meter 1"
Notes
Example 1
Example 2
Pulse valency