Input and Output wiring guidelines tables - Metasys - MS-VMA1826-x - MS-VMA1832-x - Field Device - VMA18 VAV Modular Assembly

VMA1826/1832 VAV Controller Installation Guide

Product
Variable Air Volume > Modular Assemblies > VMA18 VAV Modular Assembly
Document type
Installation Guide
Document revision
K
Revision date
2019-10-18
docpartnumberlabel
Part No.
Part number
24-10143-373
Table 1. I/O terminal blocks, functions, ratings, requirements, and cables

Terminal block label

Terminal labels

Function, ratings, and requirements

To determine wire size and maximum cable length

UNIVERSAL

(Inputs)

+15 V

15 VDC Power Source for active (3-wire) input devices connected to the Universal INn terminals.

Provides 35 mA total current.

Same as (Universal) IN n.

Note: Use 3-wire cable for devices that source power from the +15 V terminal.

IN n

Analog Input - Voltage Mode (0–10 VDC)

10 VDC maximum input voltage

Internal 75k ohm Pulldown

See Guideline A in Table 2.

Analog Input - Resistive Mode (0–600k ohm)

Internal 12 V, 15k ohm pull up

Qualified Sensors: 0–2k potentiometer,

RTD (1k Nickel [ Johnson Controls sensor],

1k Platinum, and A99B Silicon Temperature Sensor)

Negative Temperature Coefficient (NTC) Sensor

10K Type L (10K JCI Type II is equivalent to Type L) or 2.252K Type II

See Guideline A in Table 2.

Binary Input - Dry Contact Maintained Mode

1 second minimum pulse width

Internal 12 V, 15k ohm pull up

See Guideline A in Table 2.

ICOM n

Universal Input Common for all Universal INn terminals

Note: All Universal ICOMn terminals are isolated from all other commons on the -0 models. The -1 model ICOMn terminals are isolated from FC BUS COM terminals only.

Same as (Universal) IN n.

BINARY

(Outputs)

OUT n

Binary Output - 24 VAC Triac (Internal Power)

Sources internal 24 VAC power (24~ HOT)

See Guideline C in Table 2.

OCOM n

Binary Output - 24 VAC Triac (Internal Power)

Connects OCOMn to 24~ COM when activated.

Internal Power Source:

30 VAC maximum voltage to load

0.5 A maximum output current

1.3 A at 25% duty cycle

40 mA minimum load current

See Guideline C in Table 2.

CONFIGURABLE

(Outputs)

OUT n

Analog Output - Voltage Mode (0–10 VDC)

10 VDC maximum output voltage

10 mA maximum output current

External 1k to 50K ohm load required

See Guideline A in Table 2.

Binary Output 24 VAC Triac

Connects OUT to OCOM when activated.

External Power Source:

30 VAC maximum voltage to load

0.5 A maximum output current

1.3 A at 25% duty cycle

40 mA minimum load current

See Guideline C in Table 2.

OCOM n

Analog Output Signal Common: All Configurable Outputs defined as Analog Outputs share a common, which is isolated from all other commons except the Binary Input common.

Same as (Configurable) OUT n.

Binary Output Signal Common: All Configurable Outputs defined as Binary Outputs are isolated from all other commons, including other Configurable Output commons.

Note: Table 2 defines cable length guidelines for the various wire sizes that may be used for input and output wiring.
Table 2. Cable length guidelines for recommended wire sizes

Guideline

Wire size/Gauge and type

Maximum cable length and type

Assumptions

A

1.0 mm (18 AWG) stranded copper

457 m (1,500 ft) twisted wire

100 mV maximum voltage drop

Depending on the cable length and the connected input or output device, you may have to define an offset in the setup software for the input or output point.

0.8 mm (20 AWG) stranded copper 297 m (975 ft) twisted wire

297 m (975 ft) twisted wire

0.6 mm (22 AWG) stranded copper 183 m (600 ft) twisted wire

183 m (600 ft) twisted wire

24 AWG stranded copper 107 m (350 ft) twisted wire

107 m (350 ft) twisted wire

B

1.0 mm (18 AWG) stranded copper

229 m (750 ft) twisted wire

100 mV maximum voltage drop

Depending on the cable length and the connected input or output device, you may have to define an offset in the setup software for the input or output point.

0.8 mm (20 AWG) stranded copper 297 m (975 ft) twisted wire

137 m (450 ft) twisted wire

0.6 mm (22 AWG) stranded copper 183 m (600 ft) twisted wire

91 m (300 ft) twisted wire

24 AWG stranded copper 107 m (350 ft) twisted wire

61 m (200 ft) twisted wire

C

See Figure 1 to select wire size/gauge.

Use stranded copper wire.

See Figure 1 to determine cable length.

Use twisted wire cable.

N/A

Figure 1. Maximum wire length by current and wire size