ASCO 300 Series D Frame 3-Phase Wiring Diagrams

Product Overview and Features

This document provides detailed wiring diagrams and technical information for ASCO 300 Series D Frame 3-Phase Automatic Transfer Switches (ATS) with Group G controls, available in ratings from 30 to 230 Amps.

Key Features:

Engine Control Contacts
Load Disconnect Feature
Common Alarm & Not In Auto Signaling Features
In-Phase Transfer Feature for Load Transfer
Source Availability Signals
External Power Supply Compatibility
Load Current Metering
Non-Automatic (Manual) Operation
Remote Control Features
Advanced-Function Software Bundle

Wiring Diagram Components and Connections

This document details the electrical schematics and physical layout for ASCO 300 Series D Frame Automatic Transfer Switches. It covers various aspects of the system's wiring and connectivity.

Field Connections

The diagrams illustrate the various field connection points and terminal designations for the ATS. This includes general terminal connections, connections for optional accessories like the 23GB (Load Current Metering), external accessory connections, external neutral transfer connections, and external source transfer connections. Specific terminal labels such as EA, EB, EC, EN, NN, LA, LB, LC, LN are shown connected to internal components and external sources/loads.

Main Power Poles and TS Operator Circuit

The schematics depict the main power pole configurations for the transfer switch, differentiating between EMERGENCY and NORMAL sources and the LOAD connection. It also details the TS (Transfer Switch) Operator Circuit, showing the control logic, solenoids, and contacts that manage the transfer operation. The operator circuit includes components like CP (Control Panel), PV (Solenoid), CR (Coil), and TS control contacts, indicating their states (e.g., CLOSED BEFORE, CLOSED) and terminal assignments for test and adjustment procedures.

Transfer Switch Test & Adjustment Procedure

This procedure specifies control cut-off (contact opening) setting and provides terminal assignments for testing and adjustment.

Source, Load, and Control Circuits

This section details the electrical circuits for sensing the normal and emergency power sources, the connections to the load terminals, and the control signals and indications.

Normal and Emergency Source Circuits

Diagrams show 3-phase sensing for the normal source (connected to NA, NB, NC) and single-phase sensing for the emergency source (connected to EB, EC). These circuits feed into the control panel.

Load Terminal Circuits

Illustrates the connections for the load (LA, LB, LC, LN) to the transfer switch.

Control Signals & Indication

Depicts connections for control panel signals and indications, including auxiliary contacts from the transfer switch.

Optional Accessory 23GB (Load Current Metering)

Details the integration of the 23GB accessory for load current metering. This involves Current Transformers (CTs) with specific ratios for different switch ratings:

Switch Rating	CT Ratio
30A	50:5A
70A	75:5A
100A	100:5A
150A	150:5A
200A	200:5A
230A	250:5A

Connections are made via terminal blocks (TB1) and the current sensing module (SB).

Physical Layout and Wiring

Physical Diagram

Provides a visual representation of the physical layout within the ATS enclosure. It shows the placement of key components such as the CTs (CX1, CX2, BX1, BX2, AX1, AX2), TS Coil, Group G controller, and optional accessories like the 23GB (Current Sensing Module), 135L (Power Meter), 18RX (Relay Expansion Module), 1UP (Uninterruptible Power Supply), and 18RX1 (Relay Expansion Module). Terminal blocks (TB1, TB1A, TB2) for accessory connections are also shown, along with optional neutral configurations and a bonding strap for grounding. The diagram also illustrates connection sequences for multiple accessories.

Wire Run Listing

This section provides a detailed listing of wires used in the assembly, organized by harness and connection points. It includes harness locators (e.g., HARNESS 337782-003, HARNESS 309320-005), wire numbers, connection points (e.g., TS-8.P-1, Px-1,Jx-1, CT-CX1, SB-1), wire gauge (CLR AWG), and specific connections for the 23GB accessory and other optional modules. It lists wires for "ADDITIONAL WIRES", "REMOVE WIRES", and specific connections to terminals like SB, CP(23G)-TB1, and CTs.

Document Information

The document includes a revision history table detailing changes made via Engineering Change Notices (ECNs), including dates and approvers. It is produced by ASCO Power Technologies, L.P. in Florham Park, New Jersey, USA.

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