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コントロールユニット Belimo AF120-S USのPDF マニュアルをオンラインで閲覧またはダウンロードできます。Belimo AF120-S US 11 ページ。 On-off, spring return fail-safe, 120 or 230 vac
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General Wiring Instructions
WARNING The wiring technician must be trained and experi-
enced with electronic circuits. Disconnect power supply
before attempting any wiring connections or changes. Make
all connections in accordance with wiring diagrams and follow
all applicable local and national codes. Provide disconnect
and overload protection as required. Use copper, twisted pair,
conductors only. If using electrical conduit, the attachment to
the actuator must be made with flexible conduit.
Always read the controller manufacturer's installation lit-
erature carefully before making any connections. Follow
all instructions in this literature. If you have any questions,
contact the controller manufacturer and/or Belimo.
Transformer(s)
The AF24 . . actuators require a 24 VAC class 2 transformer
and draws a maximum of 10 VA per actuator. The actuator
enclosure cannot be opened in the field, there are no parts or
components to be replaced or repaired.
– EMC directive: 89/336/EEC
– Software class A: Mode of operation type 1
– Low voltage directive: 73/23/EEC
CAUTION: It is good practice to power electronic or digital
controllers from a separate power transformer than that used
for actuators or other end devices. The power supply design
in our actuators and other end devices use half wave rectifica-
tion. Some controllers use full wave rectification. When these
two different types of power supplies are connected to the
same power transformer and the DC commons are connected
together, a short circuit is created across one of the diodes in
the full wave power supply, damaging the controller. Only use
a single power transformer to power the controller and actua-
tor if you know the controller power supply uses half wave rec-
tification.
Multiple Actuators, One Transformer
Multiple actuators may be powered from one transformer provid-
ed the following rules are followed:
1. The TOTAL current draw of the actuators (VA rating) is
less than or equal to the rating of the transformer.
2. Polarity on the secondary of the transformer is strictly fol-
lowed. This means that all No. 1 wires from all actuators
are connected to the common leg on the transformer and
all No. 2 wires from all actuators are connected to the
hotleg.
Mixing wire No. 1 & 2 on one leg of the trans-
former will result in erratic operation or failure of the actua-
tor and/or controls.
Multiple Actuators, Multiple Transformers
Multiple actuators positioned by the same control signal may
be powered from multiple transformers provided the following
rules are followed:
1. The transformers are properly sized.
2. All No. 1 wires from all actuators are tied together and tied
to the negative leg of the control signal. See wiring diagram.
Installation Instructions
Wire Length for AF... Actuators
Keep power wire runs below the lengths listed in the Fig. H. If
more than one actuator is powered from the same wire run,
divide the allowable wire length by the number of actuators to
determine the maximum run to any single actuator.
Example: 3 actuators, 16 Ga wire
350 Ft ÷ 3 Actuators = 117 Ft. Maximum wire run
Maximum Wire Length:
Wire Size
Max. Feet.
12 Ga
900 Ft.
14 Ga
550 Ft.
16 Ga
350 Ft.
Fig. H
Wire Type and Wire Installation Tips
For most installations, 18 or 16 Ga. cable works well with the
AF24. . actuators. Use code-approved wire nuts, terminal
strips or solderless connectors where wires are joined. It is
good practice to run control wires unspliced from the actuator
to the controller. If splices are unavoidable, make sure the
splice can be reached for possible maintenance. Tape and/or
wire-tie the splice to reduce the possibility of the splice being
inadvertently pulled apart.
The AF24... proportional actuators have a digital circuit that is
designed to ignore most unwanted input signals (pickup). In
some situations the pickup may be severe enough to cause
erratic running of the actuator. For example, a large inductive
load (high voltage AC wires, motors, etc.) running near the
power or control wiring may cause excessive pickup. To
solve this problem, make one or more of the following
changes:
1. Run the wire in metallic conduit.
2. Re-route the wiring away from the source of pickup.
3. Use shielded wire (Belden 8760 or equal).
shield to an earth ground. Do not connect it to the actua-
tor common.
Initialization of the AF24-SR US, and AF24-MFT US
When power is initially applied, the actuator will first release its
manual preload position (This assumes a manual position has
been set). The actuator will then rotate to the full fail-safe posi-
tion. At this point the microprocessor recognizes that the actua-
tor is at full fail-safe and uses this position as the base for all of
its position calculations. The microprocessor will retain the ini-
tialized zero during short power failures of up to 20 seconds.
The AF24-MFT US will also return to its position prior to the
20-second-or-less power loss. For power failures greater than
20 seconds, the actuator would naturally return to its full fail-
safe position prior to the microprocessor losing its memory.
The actuator will also re-initialize if the manual position mecha-
nism is used.
General Wiring
Wire Size
Max. Feet
18 Ga
225 Ft.
20 Ga
125 Ft.
22 Ga
60 Ft.
Ground the
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