ASCO Series D386 Non-Automatic Transfer Switch: Wiring Diagrams and Technical Specifications

Overview

This document provides detailed wiring diagrams, technical specifications, and operational notes for the ASCO Series D386 Non-Automatic Transfer Switches, rated for 30, 70, 100, 150, 200, and 230 Amperes, equipped with Group I Controls.

General Information and Notes

The following general notes and factory settings are applicable to the ASCO Series D386 transfer switches.

General Notes

1. Switch shown de-energized and connected to the normal source.
2. Device symbols and designations are in accordance with NEMA Publication ICS 1-1983, Part 1-101A.
3. All wiring is #16 AWG, tinned, stranded copper unless otherwise indicated.
4. O on terminal blocks indicates available field connection point.
5. ● on terminal blocks indicates factory connection point.
6. Control and accessory wiring is routed in accordance with ASCO Assembly Procedure GS451261.
7. An operator's manual is furnished with each transfer switch. Refer to this publication prior to installation and operation of the unit.
8. Ground strap on control panel is affixed to chassis (enclosure) at the lower left control panel mounting stud.

Field Connections

This section illustrates the basic field connections for the transfer switch. Key components include the Control Panel (CP), Operator Panel (OP), and the Transfer Switch (TS) itself. It shows connections for auxiliary contacts (Feature 14A, 14B) which are rated for 10 Amps at 32VDC or 480VAC, and are typically closed on Normal (14A) or Emergency (14B) source connection, respectively. Load disconnect contacts are rated for 5 Amps resistive at 28VDC or 120VAC maximum. Optional accessories, such as the ACC. 72A Serial Communications option for communicating with Group I Control Panels, are also indicated.

Standard Factory Settings for Control Panel

The standard factory settings for the DIP switches S1, S2, and S3 on the control panel are illustrated. These switches control various operational parameters.

S1: Typically used for Normal Source Voltage (PU/N) pickup settings. Factory setting for 90% pickup is with Actuator 3 ON; 95% pickup is with Actuator 3 OFF.
S2: Typically used for Emergency Source Voltage (PU/N) pickup and dropout settings. Factory settings are 90% pickup and 75% dropout (non-adjustable).
S3: Typically used for Emergency Source Frequency pickup settings. Factory setting is 95% (non-adjustable).

A warning ⚠️ is provided: "Any change in these settings may affect the normal operation of the transfer switch."

Additional notes on factory settings include: P1 (Timer E/N) set up for full CCW, P2 (Timer N/E) set up for full CCW. One (1) Form C contact indicates connection to Normal (14A) and one (1) for Emergency (14B), rated 10 Amps, 32VDC, 480VAC. Signal light PL1 (Green LED) indicates connection to Normal source (Std. Feat. 9A). Signal light PL2 (Red LED) indicates connection to Emergency source (Std. Feat. 9B). Additional auxiliary contacts are available as options.

Optional Accessories

The following optional accessories are available for the Series D386 transfer switches:

ACC. 6Q: Key operated transfer control switch for transferring to Normal or Emergency. Features a three-position momentary spring return to center, with the key removable in the center position.
ACC. 9C: Signal light (PL3 Green LED) indicates Normal source is available.
ACC. 9D: Signal light (PL4 Red LED) indicates Emergency source is available.
ACC. 27: In-phase transfer control logic to initiate an in-phase transfer of loads between live sources. This prevents nuisance tripping of circuit breakers and potential damage from out-of-phase transfers. Activated by a DIP switch on the control panel (factory set as disabled). Refer to the operator's manual for control panel settings.
ACC. 31: One set of Form C contacts (1 N/O & 1 N/C) that change position on activation of a selectable time delay before transfer (LD TDBT). These contacts reset either immediately following transfer or after the same delays set for pre-signal before transfer. Selectable as 0, 3, 10, or 20 seconds (factory set at 0). Output contacts are rated 5 Amps resistive at 28VDC or 120VAC maximum.
ACC. 37B: Extension harness for units shipped open to accommodate customer mounting of controls and switch. The extension is 72 inches (1828mm) long.
ACC. 43M: Provisions for a customer-supplied 3-position selector switch. Position 1: Local control enable. Position 2: Remote control transfer to Normal. Position 3: Remote control transfer to Emergency.
ACC. 72A: Serial communications interface. Provides an RS-485 serial interface to the control panel for remote monitoring and control from ASCO communications-based products. Notes specify field wiring requirements using shielded, twisted-pair cables (e.g., BELDEN 9842 or ALPHA 6202C).

Catalog Number Explanation

The following tables detail the catalog number structure and provide explanations for the various codes used.

Base Catalog Number Chart

BASE CATALOG NUMBER	TS CATALOG TYPE	NEUTRAL TYPE	PHASE	FRAME TYPE	CONTROLLER CODE	OPTIONAL ACCESSORY	ENCLOSURE CODE
D386	TS	BLANK (NONE)	1 (1PH)	D	ABCDEF HJKLMNPQR	BLANK (NONE)	BLANK (OPEN TYPE)
		C (SOLID)	2 (2 WIRE)				1 (GENERAL PURPOSE, INDOOR)
		B (SWITCHING)	3 (3 WIRE)				3R (OUTDOOR, RAINPROOF, SLEET & ICE RESISTANT)
		F (OVERLAPPING)					G (INDOOR/OUTDOOR, WATERTIGHT & DUSTTIGHT)

Explanation of Catalog Number Codes

CATALOG NUMBER CODE	DESCRIPTION	CODE
FRAME TYPE	D	"D" FRAME, GROUP 1 CONTROLS
TS TYPE	TS	SERIES D386 TS, 1PH, 30-230 AMPS
NEUTRAL TYPE	BLANK	NONE
	C	SOLID
	B	SWITCHING CONTACTS
	F	OVERLAPPING CONTACTS
PHASE	1	SINGLE PHASE
	2	2 WIRE
	3	3 WIRE
CONTROLLER CODE	ABCDEF HJKLMNPQR	(See ASCO Documentation for full details)
OPTIONAL ACCESSORY	BLANK	NONE
	A-R	(Specific accessory codes)
ENCLOSURE CODE	BLANK	OPEN TYPE (NO ENCLOSURE)
	1	GENERAL PURPOSE, INDOOR
	3R	OUTDOOR, RAINPROOF, SLEET & ICE RESISTANT
	G	INDOOR/OUTDOOR, WATERTIGHT & DUSTTIGHT
VOLTAGE CODES	115, 120, 208, 220, 230, 240, 380, 400, 415, 440, 460, 480, 550, 575, 600*	(Nominal Voltage)
NEUTRAL TYPE	C	SWITCHING
CODE	L	12 (50 or 60 Hz)
TYPE		INDOOR, INDUSTRIAL ENVIRONMENTS, OILTIGHT & DUSTTIGHT

* 200 & 230 Amp sizes are 480V max.

Wiring Diagrams

Main Power Poles

This diagram illustrates the main power pole connections for the transfer switch. It shows the Emergency power poles (ELI, EL2, ELO) and the Normal power poles (NL1, NL2, NLO). These are connected to the Load terminals (LLI, LL2, LLO). The diagram also references "Optional Neutral Types" which include None, Switching Contacts, Overlapping Contacts, and Solid Bus Plate, as detailed in the catalog number codes. The note "ATS shown closed on Normal source" indicates the default state.

TS Operator Circuit

The TS Operator Circuit diagram shows the connections for the transfer switch's operational control. It depicts the Normal and Emergency sources feeding into the transfer switch (TS). The control circuit involves the Control Panel (CP), the TS solenoid coil, and various control contacts. Terminal designations like 6-7, 69-70, 8-9, 71-72 are shown for TS Control Contacts related to solenoid position. The diagram also notes that the Transfer Switch Test & Adjustment Procedure specifies control cut-off (contact opening) setting.

Source and Load Circuits

These diagrams show the simplified circuit layouts for Normal Source, Emergency Source, and Load Terminals. Each section illustrates the connection points to the Control Panel (CP) and the respective power poles (NL for Normal, EL for Emergency, LL for Load). For example, the Normal Source Circuits show NL1, NL2, NLO connected to CP via specific terminals. Similarly, Emergency Source Circuits show EL1, EL2, ELO, and Load Terminal Circuits show LL1, LL2, LLO.

Control Signals & Indication

This section details the control signals and indication features of the transfer switch.

Indication Lights:

PL1 (Feature 9A): Load Connected to Normal (Green LED).
PL2 (Feature 9B): Load Connected to Emergency (Red LED).
PL3: Normal Source Available (Green LED) - Optional ACC. 9C.
PL4: Emergency Source Available (Red LED) - Optional ACC. 9D.

Selector Switch (SS): Controls transfer operations. Positions typically include Normal, Emergency, and Center (Test - TD Bypass).
Control Panel (CP) Connections: Shows connections for various control inputs and outputs, including those for optional accessories like ACC. 43M (Customer Supplied Selector Switch) and ACC. 9C/9D (Indicator Lights).
Transfer Switch (TS) Contacts: Depicts contacts related to transfer operations, such as those for transferring to Normal or Emergency, and common contacts.

Wire Run Listings

The following tables provide detailed wire run listings for the standard transfer switch harness and optional accessories.

Wire Run Listing - Standard Transfer Switch Harness (30-230 Amps)

WIRE NO.	HARNESS LOCATOR	(P) MAIN TS	CLR	AWG
1	TS-8,P-	1	J-1,CP-P1-8	20
2	TS-A,P-2	2	J-2,CP-P1-15	20
3	TS-6,P-3	3	J-3,CP-P1-2	20
4	TS-3,P-4	4	J-4,CP-P1-4	20
5	TS-B,P-5	5	J-5,CP-P1-17	20
6	TS-5,P-6	6	J-6,CP-P1-12	20
7	TS-4,P-7	7	J-7,CP-P1-7	20
8	TB-14,P-8	8	J-8,CP-P2-2	20
9	TB-15,P-9	9	J-9,CP-P2-3	20
10	TS-17,P-10	10	J-10,CP-P2-8	20
11	TS-2,P-11	11	J-11,CP-P1-10	20
12	TS-1,P-12	12	J-12,CP-P1-	20
13	TS-16,P-13	13	J-13,CP-P2-9	20
14	TS-18,P-14	14	J-14,CP-P2-10	20
15	TS-70,P-15	15	J-15,CP-P1-5	20
16	TS-72,P-16	16	J-16,CP-P1-13	20
17	TS-4,TS-9		J-17,CP-P2-1	20
18	TS-7,TS-1		J-18,CP-P1-14	20
20	TS-3,TS-69		J-19	20
21	TS-5,TS-71		J-20	20
24	TB-16,P-17		J-21	20
25	TS-19,P-18		J-22	20
26	TS-20,P-19		J-23	20
27	TS-21,P-20		J-24	20
28	TS-22,P-21
29	TS-NN,P-22
30	TS-EN,P-23
31	TS-LN,P-24

DEAD END WIRES: 11 TS-2,P-11; 25 TS-19,P-18; 27 TS-21,P-20

Optional ACC. 11CD Wire Run Listing

WIRE NO.	HARNESS LOCATOR	(P3) DOOR CONTROLS & INDICATORS	CLR	AWG	WIRE NO.	HARNESS LOCATOR	(CP-4,TMR-3)	CLR	AWG
28	CP-4,TMR-3		16		29	CP-5,TMR-5		16
30	CP-14,TMR-2		16		31	CP-15,TMR-1		16

Optional ACC. 6Q Wire Run Listing

WIRE NO.	HARNESS LOCATOR	CLR	WIRE NO.	HARNESS LOCATOR	CLR
140	P3-5,PL1(-)	22	141	P3-8,PL1(+)	22
142	P3-6,PL2(-)	22	143	P3-7,PL2(+)	22
144	P3-9,PL3(-)	22	145	P3-10,PL4(-)	22
146	P3-11,PL3(+)	22	146	PL3(+),PL4(+) *	22
147	CP-6,SS-13	22	148	CP-10,SS-23	22
149	CP-7,SS-14	22	149	SS-14,SS-24	22

* NOTE: CONNECTIONS ARE OPTIONAL FOR ACC. 9C, 9D.
OPTIONAL ACC. 6Q: WITH 60 KEY OPTION REMOVE WIRES 147, 148, 149.
ADD WIRES: 147 CP-6,SS-1NO; 148 CP-10,SS-2NO; 149 CP-7,SS-1COM; 149 SS-1COM,SS-2COM.

Physical Diagram and Layout

This section provides a physical view of the transfer switch and its components.

Enclosure View

The "TS (Transfer Switch) View from Inside Front" diagram shows the physical arrangement of the transfer switch for 30, 70, 100, 150, 200, & 230 Amps. It illustrates the main power terminals for Emergency (ELI, EL2, ELO), Normal (NL1, NL2, NLO), and Load (LLI, LL2, LLO). The TS Coil and standard transfer switch harness connections are also depicted. A bonding strap is noted for grounding.

Door (Inside) View

The inside of the enclosure door features the "Operator Controls" panel. This panel includes indicator lights:

PL1: TS Connected to Normal (Green)
PL2: TS Connected to Emergency (Red)
PL3: Normal Source Available (Green)
PL4: Emergency Source Available (Red)

It also includes the Selector Switch (SS) for transfer control (Test - TD Bypass). Below this is the "Group 1 Control Panel" (CP) with its terminal designations (P1, J1, P2, J2, CP-J4, CP-P4, etc.). The diagram also shows the ASCO Optional Serial Communication Device, including its module and connections (72A-P1, 72A-J1, 72A-J2), and provisions for ACC. 43M (Customer Supplied).

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