M-Bus-Module WZU-Mx
Installation and Operating Guide
M-Bus-Module WZU-MB / MI
Subject to changes
Page 9 / 10
Number of “MI” modules per UH50
An “MI” module is only permissible in slot
Module 1
Life of the module battery
5 years of ope 1 year storage duration;
if the M-bus voltage is applied for at least 90% of the operating
time, the battery life increased to 10 years
Standard for pulse inputs
Class IB per EN 1434-2
Frequency
max. 10 Hz
Pulse duration (low)
≥ 50 ms
No-pulse duration (high)
≥ 50 ms
Pulse value
0.01 liters / pulse to 10,000.00 liters / pulse, in steps of 0.01 liters
/ pulse
Display and output in the UH50
in m
3
, 7-digit;
acc. to parameter setting with or without 1 decimal place
Polarity
yes, must be correct, if transmitter is of type “open collector”
Electrical isolation
from the meter:
yes
from the M-bus inputs:
no
Output voltage
Approximately 3.3 V
Internal resistance
approx. 1 M
Ω
Source current
approx. 3 µA
Pulse input closed (low)
Switching threshold low
< 0.2 V
Resistance
< 50 k
Ω
Pulse input open (high)
Switching threshold high
unconnected collector
Resistance
≥ 6 MΩ
Connection
Insulation stripping length 5 mm
Connection
- rigid or flexible, 0,25...0,75 mm²
- flexible with ferrules, 0,25...0,75 mm²
Permissible cable length
max. 10 m
The cables should be as short as possible and on no account
exceed 10 m.
5.2 Parameter setting of the pulse functions
The “MI” module is supplied in “storage mode,” which means:
- the module is powered with voltage by a battery,
-
the parameters “Device number”, “Meter reading,” “Pulse value,” and “Decimal place” are zero,
- the pulse inputs are inactive.
Until the module receives parameter setting data, the input inputs remain inactive.
5.2.1 Activating pulse inputs
Put the meters into parameterization mode (see “3.2.1 Preparing parameterization”).
In the menu
Parameterization
/ submenu
Pulse input
, the values for the parameters “Device number,”
“Meter reading,” “Pulse value,” “Decimal place,” and identification of the medium type in the M-bus telegram
are defined. Parameter setting is performed separately for pulse input 1 and pulse input 2.
With the “OK” button, the entered parameters are transmitted.
