DZNT VAV / VVT Installation Guide
Page 12 of 16
Document Edition 1.2
Network & Cabling Requirements
To ensure network stability and reliable communications, particularly at high speeds on the RS-485 MS/TP networks,
it is imperative that you adhere to the following network and cabling requirements.
Item
Description
Cabling
Cabling has been simplified to use standard straight-through unshielded twisted pair (UTP) Cat3 or higher cables
(Cat5, Cat5e, Cat6) to connect boxes to boxes, and individual boxes to their thermostats.
Topology
The cabling is designed to maintain the required daisy-chain configuration even with the use of network Y’s. Each
cable provides a path to and from each device.
Max. Nodes
MS/TP: The maximum number of devices per MS/TP network is 50 without a repeater, 99 with a repeater.
Network
Terminators
No additional external Network Termination is required: this product line provides an integrated network
termination that maintains network signal integrity.
Repeater
MS/TP: A repeater (DZNR-768 or RPT-768) is not necessary unless more than 50 nodes will be installed on a
network
or
you need to extend the network beyond 2000 ft* (610 m).
* Total network length is determined by sum of cable lengths between termination boards, plus the sum of the
drop cables between termination board and thermostat.
For more information on networks, cabling and wiring please refer to
Delta Controls Wiring Guidelines
.
Cautions and Warnings
The DZNT is an electro-statically sensitive device. However, the electronics are
contained within the housing, so if sufficient care is taken in handling, ESD
protection (ground strap) should be unnecessary.
Apply a minimum 6.0 lb-in torque for tightening field wires into the terminal
blocks.
