Refrigeration Demand" Function Block; Purpose; Refrigeration Demand Relay; Refrig Demand Modulating - Siemens RMB795B Basic Documentation

"Refrigeration demand"
signal generation
Purpose and function
Configuration

Purpose

Configuration
Setting values
Siemens
Building Technologies
11.5

"Refrigeration demand" function block

11.5.1 Purpose
The function block generates a "Refrigeration demand" signal that can be used by
other devices. The refrigeration demand is provided in the form of the following
signals:
• Digital signal at output Q ("Refrigeration demand relay")
• Analog signal at output Y ("Refrigeration demand modulating")
• Bus signal ("Communication")
Refrigeration demand
Relay
Q Q Y Y
The 3 variants are described below.

11.5.2 Refrigeration demand relay

The refrigeration demand relay must be configured to a relay output N.Qx of the
RMB795B central control unit. Release for an external refrigeration source, e.g.,
can be connected to this output.
The refrigeration demand relay responds as soon as the bus requests refrigeration.
Meaning:
• Contact open =
• Contact closed
=
Main menu > Commissioning > Extra configuration > Demand for refrigeration
Operating line
Refrigeration demand
relay

11.5.3 Refrig demand modulating

In addition to the refrigeration demand relay, the refrigeration demand can be
provided at a modulating output N.Yx for other devices.
Main menu > Commissioning > Extra configuration > Demand for refrigeration
Operating line
Refrig demand
modulating
Main menu > Settings > Refrigeration demand >
Operating line
Setpoint at 0 V
Setpoint at 10 V
Limit value.
Central control unit RMB795B
Distribution zones
No refrigeration demand.
Refrigeration demand
Adjustable values / remarks
---, N.Q1, N.Q3, ... /
activation of output
Adjustable values / remarks
---, N.Y1, N.Y2
activation of output
Range
–50...+50 °C
50...500 °C
–50...+250 °C
Factory setting
12 °C
6 °C
12 °C
103 / 144
CE1P3122en
18.01.2012