Power Terminals For Ac Power; Power Terminals For 24 Vdc Power - Vaisala PR-23 Series User Manual

Terminal
41 42
51 52 53 54 55
4.2.4 Power terminals for AC power
The primary AC power is connected to a separate terminal strip 31/32/33 marked POWER in
the lower right-hand corner of the motherboard. The three terminals are marked 31/L, 32/N
and 33/ (protective earth). The power terminal 33/ is directly connected to the exposed
metal parts of the indicating transmitter DTR. Wiring to the terminals must be of min.
2
1.5 mm . The fuse voltage should be 250 V, max. size 10 A and fuse speed slow. Ensure that
the protective fuse in the building system complies with local requirements.
4.2.5 Power terminals for 24 VDC power
The DC power is connected to a terminal stripe marked POWER in the lower right-hand
corner of the motherboard. The three terminals are marked +, − and (protective earth). The
power terminal is directly connected to the exposed metal parts of the Indicating
transmitter DTR.
The 24 VDC power to this terminal stripe must be supplied from a secondary circuit which is
double or reinforced insulated from the mains supply within the limits for a limited-energy
circuit (maximum 200 VA/U) according to the IEC 61010-1.
Usage
24 V terminal for DTR internal use only.
Connecting terminal to external 24 V supply voids
the warranty. Connecting external devices to 24 V
terminal voids the warranty.
Switch inputs: switch 1 (51), switch 2 (52), switch 3 (53), switch 4 (54)
and common 3 V for all inputs (55). The switch terminals are galvanically
isolated.
Chapter 4 – Indicating transmitter DTR
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