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10.7 Building Ma na ge ment System
For connection to a Building Management System the
Remeha Gas 3002 ECO is delivered as standard with a
RS 232 connection.
The boiler is also provided with the following potential-
free contacts: - signal "low"
- signal "high"
- central alarm.
Standard the signal "low" is activated if the boiler load is
bet ween minimum and 95% and the signal "high" is acti-
vated if the boiler load is between 95% and maximum.
See also Option 6, page 16.
10.8 Frequency changer
The frequency changer controls and delivers a 3-phase
supply of 230V, by which the frequency can vary from
0 to a maximum of 60Hz. This alternation in frequency
controls the speed of the fan motor. The frequency chan-
ger is fitted in the control panel behind the front casing.
Inside the frequency changer there are two L.E.D.'s, a
green one for 'ready' and a red one for 'fault' indication.
Blinking green L.E.D. means the frequency changer is
not ready. In that case, check the link between terminal 7
and 39, and the link between terminal 20 and 28 (see
wiring diagram).
If the red L.E.D. is blinking the frequency changer fails.
This is caused by:
- Short circuit on the windings of the motor or in the
wiring to the motor.
• Check the wiring of the motor and measure the
windings of the motor.
- The motor runs heavy, through which the current
increases.
• Check if the fan runs free.
- Frequency changer is too hot.
• Check if the cooling rib is too hot and if the
frequency changer is fitted correctly to the control
panel.
By switching on/off the frequency changer will be reset.
10.6 Outputs
10.6.1 Alarm output
The boiler is fitted with a potential-free two-way contact
for the alarm or ready message. When the boiler is
locked or dead, contact 11 and 12 will be made. When
the boiler is ready, contacts 11 and 10 will be made.
The maximum load on the contact is 250V/2A.
This output is indicated by the following symbol:
10.6.2 Operating message
The boiler is fitted with two potential-free closed-circuit
contacts for the low operating message and the high
operating message. Contacts 13 and 14 are for the low
operating message, and contacts 15 and 16 for the high
operating message. The moment at which a switch is
made from low to high can be programmed at the service
level (see paragraph 7.3.3, option 6).
The symbol for this output is:
10.6.3 External gas valve
If required, an external gas valve can be connected to
terminals 17 and 18. 230V is applied to these terminals
as soon as the fan starts to operate. When the fan
switched off, the voltage is also disconnected.
The maximum power take-up for the gas valve is 0.1A.
The symbol for this output is:
10.6.5 Extra 230V connection
On terminals 8 and 9, the external power supply is once
again diverted outwards for the connection of external
components such as relays and pumps. The voltage on
these terminals is
not switched off by the main switch
on the panel
. This voltage is also neither fused nor
filtered.
The maximum current across these terminals is 10A, but
will depend on the value for which the power supply to
the boiler is fused. In the switch panel there is a little
free
space for the possible installation of an extra relay.
The symbol for this output is:
