Communication bus and supply power table - Metasys - MS-VMA1826-x - MS-VMA1832-x - Field Device - VMA18 VAV Modular Assembly

VMA1826/1832 VAV Controller Installation Guide

Brand
Metasys
Product name
VMA18 VAV Modular Assembly
Document type
Installation Guide
Part number
24-10143-373
Document revision
K
Revision date
2019-10-18
Language
English
Table 1. Communication bus and supply power terminal blocks, functions, ratings, requirements, and cables

Terminal block/Port label

Terminal labels

Function, electrical ratings/Requirements

Recommended cable type

N2/FC BUS 2

+

-

N2/FC Bus Communications

Use existing cable or 18 AWG

COM

Signal Reference (Common) for bus communications

SHLD

Isolated terminal (optional shield drain connection)

SA BUS

+

-

SA Bus Communications

0.6 mm (22 AWG) stranded, 4-wire (2 twisted-pairs), shielded cable recommended

Note: The + and - wires are one twisted pair, and the COM and SA PWR are the second twisted pair.

COM

SA Bus Signal Reference and 15 VDC Common

SA PWR

15 VDC Supply Power for Devices on the SA Bus

TSTAT

TSTAT

RJ-45 8-Position Modular Connector provides +15 VDC Power for:

  • BTCVT 3
  • MAP Gateway
  • VAV Balancing Tool
  • One-to-One Wireless Receiver

24 AWG 3-pair CAT 3 Cable <30.5 m (100 ft)

24~

HOT

24 VAC Power Supply - Hot

Supplies 20–30 VAC (Nominal 24 VAC)

0.8 mm to 1.0 mm²

(20 to 18 AWG) 2-wire

COM

24 VAC Power Supply Common The -0 models isolate this terminal from all other commons.

The -1 models only isolate this terminal from the FC bus common.

1 To determine wire size and cable lengths for cables other than the recommended cables, see Table 2.
2 The N2/FC Bus wiring recommendations in this table are for N2 bus communications at 9,600 baud. For more information, refer to the N2 Communications Bus Technical Bulletin (LIT-636018).
3

The MAP Gateway serves as a replacement for the BTCVT, which is no longer available for purchase, but continues to be supported on select controllers.