Wiring Variations; Input Sensor Wiring; Rtd Connections; Power Supply Wiring (Modbus) Procedure - Honeywell SMV800 Quick Start Installation Manual

An optional lightning terminal block can be installed in place of the non-
lightning terminal block for transmitters that will be installed in areas that are
highly susceptible to lightning strikes. As noted above, the loop power wiring
shield should only be connected to earth ground at the power supply end.
Wiring must comply with local codes, regulations and
ordinances. Grounding may be required to meet various
approval body certification, for example CE conformity. Refer to
Appendix A of this document for details.
The HART/DE transmitter is designed to operate in a 2-wire power/current loop
with loop resistance and power supply voltage within the operating range; see
Figure 7.
With an optional remote meter (for HART/DE), the voltage drop for this must be
added to the basic power supply voltage requirements to determine the
required transmitter voltage and maximum loop resistance. Additional
consideration is required when selecting intrinsic safety barriers to ensure that
they will supply at least minimum transmitter voltage, including the required 250
ohms of resistance (typically within the barriers) needed for digital
communications.

Wiring Variations

The above procedures are used to connect power to a transmitter. For loop
wiring and external wiring, detailed drawings are provided for transmitter
installation in
non-intrinsically safe areas and for intrinsically safe loops in hazardous area
locations.
This procedure shows the steps for connecting power to the transmitter.
Loop Wiring (HART/DE)
Step
1
See Figure 8, above, for parts locations.
Remove the end cap cover from the terminal block end of the
2
electronics housing.
3 Feed loop power leads through one end of the conduit
entrances on either side of the electronics housing. The
transmitter accepts up to 16 AWG wire. Shield of the cable to
be grounded on the supply/host side.
4 Connect the positive loop power lead to the positive (+)
terminal and the negative loop power lead to the negative (-)
terminal. Note that the transmitter is not polarity-sensitive.
5
Feed input sensor wires through the 2
connect wire.
Replace the end cap, and secure it in place.
6

Power Supply Wiring (Modbus) Procedure

1. See Figure 8, above, for parts locations. Loosen the end cap lock using
a 1.5 mm Allen wrench.
2. Remove the end cap cover from the terminal block end of the
electronics housing.
3. Feed twisted pair shielded power supply leads through one end
of the conduit entrances on either side of the electronics housing.
The transmitter accepts up to 16 AWG wire. Shield of the cable
to be grounded on the Supply/Host side.
4. Connect the positive power supply lead to the positive (+)
terminal (Terminal #1) and negative power supply lead to the
negative (-) terminal (Terminal #2). Note that the transmitter is
not polarity-sensitive.
5. Modbus communication wires can be fed through the same
conduit that is being used for feeding power supply inputs. For
details related to Modbus connection refer to Table 3 and the
section on SMV Modbus Half-Duplex Modbus (RS-485) Wiring
Procedure.
6. Feed input sensor wires through the 2nd conduit entrance and
connect wire.
7. Replace the end cap, and secure it in place.
Action
nd
conduit entrance and

Input Sensor Wiring

Connect the input sensors as shown in
Figure 9: Thermocouple connections

RTD Connections

o Resistance temperature detector (RTD) measurements use the 3 or 4
wire approach. The transmitter determines by itself if a 3 or 4 wire
RTD is connected when powered up.
Figure 10: RTD connections
Figure 11: Wiring details for SMV Modbus Terminal block

Table 3: Wiring details for SMV Modbus Terminal block

Terminal
Number
1 Power Supply input +ve
2 Power Supply input -ve (Return)
3 Modbus (RS-485) A
4 Modbus (RS-485) B
5 Temperature Sensor Input
6 Temperature Sensor Input
7 Temperature Sensor Input
8 Temperature Sensor Input
9 Modbus (RS-485) Common
Figure 9 below:
Description