Outdoor Installation; Electrical Installation - Nederman VAC 20 Manual De Instrucciones

EN VAC 20
Noise levels for the VAC series vary according to size, site and running conditions. See
'Table 3-1: Technical data' for measured noise levels. The noise level will rise by several
dB(A) when the air flow starts getting close to the flow restrictor setting. Measurements
have been made free-field with the unit standing on a reflective base in accordance to
ISO 11201 standard. The noise levels can be several dB(A) higher in a room with hard
reflective walls. The noise level can be reduced by an optional silencer, see Figure 2 Item 1
and Section '4.1 Overview'.
6.1.2

Outdoor installation

Also consider the following if the unit is installed outdoors:
•
Cover the top of the unit to protect it from snow, rain or falling debris.
•
Avoid placing the unit against a wall directly exposed to the sun.
6.1.3

Electrical installation

Connect the motor to the start and control unit and/or optional Maintenance switch.
For electrical connections, see the start and control unit's manual and also Figure 6 and
7. Connections may vary depending on the options chosen. Connecting material such as
cables are not included with the unit.
Most failures are result from faults in the electrical equipment or connections. The motor
overload relay must be of the 'heavy start type' as some units are heavy to start. Otherwise
the motor overload may trip because of the high current and the long time spent in the
Y-mode.
NOTE! Electrical installation must be made by a qualified electrician.
NOTE! National and local electric regulations must be followed.
Start and control units from Nederman have terminals for easy connection of all control
cables. If other equipment is used, this equipment must be similarly equipped and
connected for the guarantee of the VAC 20 unit to be valid.
ASC by PLC
For connecting the VAC to be run using ASC by PLC in the HV control panel, see wiring
diagram figure 6.
ASC by optional adaption kit
For connecting the VAC to be run using the adaption kit, with the optional components for
when not using ASC by PLC, see wiring diagram figure 7.
NOTE! The current transformer is to be connected to the relay box prior to starting the
vacuum unit. Otherwise, the transformer may be ruined.
The current transformer monitors the motor current for phase L1. The signal is hard-wired
to the relay box where it passes through two current sensing relays called MAX and MIN.
See the left part of Figure 18.
The MIN relay will be activated if the current is smaller than a set minimum value (opening
the valve).
The MAX relay is activated if the current is higher than a set maximum value (closing
the valve). If the current is within the 'dead band' between the minimum and maximum
settings, no relay is activated and the valve is static.
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