Auxiliary Power; Specifications (Per Section 1.3); M350 V3 Vt Inputs - Va, Vb, Vc, Vn (See Appendix A1 And Section 1.3); M350 A3 Ct Inputs - Ia, Ib, Ic (See Appendix A1 And Section 1.3) - Bitronics M350 User Manual

3.1 Auxiliary Power

The M350 meters are powered by connections to L1(+) and L2(-). A Green LED
Power (PWR) indicator is provided on the rear panel to indicate that the unit is
powered ON. It is located on the right of the rear panel.

3.1.1 Specifications (per section 1.3)

Power Supply Input (Auxiliary) Voltage – terminals L1(+) and L2(-)
Nominal:
Operating Range:
3.2 M350 V3 VT Inputs – VA, VB, VC, VN (See Appendix A1 and Section 1.3)
The M350 V3 meter voltage (VT) signal inputs are connected to terminals 3-6 (see
Appendix A1 for specific wiring configurations). Voltage signals are measured using a
12M ohm resistor divider with a continuous voltage rating of 7kV. This ideal
impedance provides a low burden load for the VT circuits supplying the signals.
Grounding of VT signals per ANSI/IEEE C57.13.3-1983 is recommended. The polarity
of the applied signals is important to the function of the instrument.
3.3 M350 A3 CT Inputs – IA, IB, IC (See Appendix A1 and section 1.3)
The M350 A3 can be connected directly to a current transformer (CT). The Current
(CT) signal inputs are connected to terminals 7-12.
Several hardware options are offered for the M650 current inputs. Distinctions are
based on the current option ordered and the physical constructions.
The 1 Amp and 5 Amp current inputs, current input options 1 and 5 respectively,
feature 10-32 terminals to assure reliable connections. This results in a robust current
input (CT) connection with negligible burden to ensure that the user's external CT
circuit can't ever open-circuit, even under extreme fault conditions. Grounding of CT
signals per ANSI/IEEE C57.13.3-1983 is required.
Current inputs, option 1: 1 Amp input with internal current isolation transformer,
constructed with 10-32 studs as the current terminals. (See Figure 3A for the
physical construction shown for the current terminals). It is intended that this
meter connect to the output from the secondary of permanently installed Current
Transformers (CTs).
WARNING: DO NOT loosen existing 10-32 hardware that secures the current input
studs to the back panel. When making connections to the current input studs, use #10
ML0038 September 27, 2017
48-250V dc, 69-240V ac (50/60Hz)
36-300V dc, 55-275V ac (45-65Hz)
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Copyright 2017 Bitronics, LLC