The DL305 series is a small modular PLC that has been marketed by various name brand PLC manufacturers for over 20 years. This Koyo design revolutionized the small PLC market, and is still a good performer and a great value.
- 2 types of CPU are available according to programming language.
 SA: Stage type
 SR: Relay symbol type
- Module addition: Up to 8 slot
- Maximum I/O points: 168 points
- Program memory: 512 to 3.7 K
- Data memory: 192
NOTE:Completion of Production of this series is scheduled for March 2021.


  • Three standard CPUs, including the D3-350 with PID control and two communication ports
  • 5, 8 and 10 slot bases
  • 110/220VAC or 24VDC power supply
  • AC, DC inputs
  • AC, DC, and relay outputs
  • 8 or 12-bit analog input/output
  • Specialty modules include ASCII/BASIC module, high-speed counter, and communication interface module

Information of Model Numbers

CPU Module SA type

Model Numbers Overview
SA-21-1 【Memory 】1.5 K
【maximum input/output】168 points
D3-330P 【Memory 】3.7 K
【maximum input/output】168 points

CPU Module SR type

Model Numbers Overview
SR-21-1 【Memory 】1.7K
【maximum input/output】168 points
D3-330 【Memory 】3.7 K
【maximum input/output】168 points
D3-340 【Memory 】3.7 K
【maximum input/output】168 points build-in RS-232C 2 points

CPU Module DL (S) Type

Model Numbers Overview
D3-350 【Memory 】14.8 K port 1: RS-232C, port 2: RS-232C/422

Self-powered CPU Module

Model Numbers Overview
D3-05B-1 【Power Source Type】110/220 V AC
【Number of Slots】5
D3-05BDC 【Power Source Type】24 V DC
【Number of Slots】5
D3-08B-1 【Power Source Type】110/220 V AC
【Number of Slots】8
E-03B 【Power Source Type】100/200 V AC
【Number of Slots】10
D3-10B-1 【Power Source Type】110/220 V AC
【Number of Slots】10
D3-10BDC 【Power Source Type】24 V DC
【Number of Slots】10

Base Expansion Cable

Model Numbers Overview
D3-EXCBL Cable length 0.5 m

Extension IO module Input Module

Model Numbers Overview
D3-08ND2 【Input】Points:8 Function:24 V DC Source
D3-08NE3 【Input】Points:8 Function:24 V AC/DC Sync
D3-16ND2-1 【Input】Points:16 Function:24 V AC/DC Sync
D3-08NA-1 【Input】Points:8 Function:100 V AC
D3-08NA-2 【Input】Points:8 Function:200 V AC
D3-16NA 【Input】Points:16 Function:100 V AC
D3-16NE3 【Input】Points:16 Function:24 V AC/DC Sync
D3-08SIM 【Input】Points:8 Function:Simulator

Extension IO module Output Module

Model Numbers Overview
D3-08TR 【Output】Points:8 Function:Relay 4 A
D3-16TR 【Output】Points:16 Function:Relay 2 A
D3-08TD1 【Output】Points:8 Function:24 V DC Sync
D3-16TD1-1 【Output】Points:16 Function:24 V DC Sync
D3-08TA-2 【Output】Points:8 Function:100/200 V AC
D3-16TD2 【Output】Points:16 Function:24 V DC Source

Extension IO module Analog output Module

Model Numbers Overview
D3-02DA 【Function】0 to 10 V DC/4 to 20 mA

Extension IO module Special Module

Model Numbers Overview
D3-HSC High speed counter input/output

Extension IO module Special unit

Model Numbers Overview
D3-232-DCU RS232C host link (For SR type)

Associated Equipment Accessories

Model Numbers Overview
D3-FILL Dummy panel

Associated Equipment Peripheral Device

Model Numbers Overview
PC-DSOFT5 Programmer software for computer
D3-HPP For SA type Simple programmer
D3-HP For SR type Simple programmer

Associated Equipment Cable / Connector for program

Model Numbers Overview
S-30JD-T Connection cable 3 m between DOS/V and D3-232-DCU
D3-HPCBL 1.5 m cable for drawing simple programmer

Associated Equipment Maintenance Product

Model Numbers Overview
D3-D4-BAT CPU memory backup battery