Dart Controls MD plus Series Data Sheet

MD50P-420 and MD40P-420

MD50P-420

MD50E-420

MD50E-420

MD40P-420

MD plus Series Digital
Closed Loop DC Drive System

Ideal for Metering Pump and other applications
requiring an isolated 4-20mA input/output signal

The MD plus is a fi eld-programmable closed loop

DC drive system employing an advanced velocity­form PID algorithm for accurate and responsive
control. The MD plus system also feat ures a unique,
isolated 4-20mA input and output for easy integration
with existing Process Control systems.

The MD plus system is ideally suited for metering

pump applications by effi ciently combining all of
the application requirements into a single compact
package. The MD plus system not only accepts a
4-20mA signal to control the pump speed, but it also
provides a 4-20mA output signal back to the Process
Control that is proportional to the actual running
speed. Both the input and output signals are isolated
from each other and from the control itself. The MD
plus system also ha s two fi eld-programmable Form C
relay contacts that can be set to indicate a wide variety
of conditions such as the pump is running, a “fault”
condition exists, and many other events.

The MD plus system is available in both enclosed

and panel-mount versions. The MD50E-420 version
comes in a NEMA 4X enclosure complete with
an auto/off/manual switch on the cover. The 1/8
DIN MD40P-420 and ¼ DIN MD50P-420 panel­mount versions come complete with a NEMA 4X
rated faceplate, gasket kit, stainless steel mounting
hardware, and connections for an external auto/
manual switch.

STANDARD FEATURES

• 1/50 to 2.0 HP range

• Universal power supply supports 85-265 VAC input

• 1/8 or 1/4 DIN panel mount with NEMA 4X faceplate,
or NEMA 4 stand-alone enclosure

• Front panel fi eld-programming (with lock-out jumper)

• Target and actual speed can be any engineering unit
of measure

• Two alarm relay outputs (form C, 5 Amp @ 250 VAC)

• Large 1/2˝ LED display

• Master/Follower modes

• Displays set point or actual running speed

• Adjustable PID settings

AVAILABLE OPTIONS

• Custom faceplates for your Brand Name

• Pluggable euro-style terminal strip

• Provision for Remote Up/Down pushbutton switches

OPERATING SPECIFICATIONS

Ambient Temp .............................................-10º to +45º C

Line Input Frequency ........................................50/60 Hz

Overload Capacity .............................200% for 1 minute

Transducer Input .................................... 0-5 to 0-24 VDC

On-board transducer

Power Supply ..............................................5 VDC, 50mA

4-20mA input/output accuracy ...............................

±

1%

18

MD plus SERIES SELECTION GUIDE

MODEL MAX. ARM MAX
NUMBER DC AMPS H.P. INPUT OUTPUT

MD40P-420 5 ½ 120 VAC 0-90 VDC
5 1.0 240 VAC 0-180 VDC

MD50P-420 10 1.0 120 VAC 0-90 VDC
10 2.0 240 VAC 0-180 VDC

MD50E-420 10 1.0 120 VAC 0-90 VDC
10 2.0 240 VAC 0-180VDC

DIMENSIONS (INCHES)

MODEL WIDTH HEIGHT DEPTH

MD40P-420 (1/8 DIN)

Housing 3.620 1.656 4.625
Lens 4.539 2.289 0.375

MD50P-420 (1/4 DIN)

Housing 3.620 3.497 4.625
Lens 4.539 4.179 0.375

MD50E-420 (NEMA 4 enclosed)

Same dimensions as MD3E on catalog page 17

APPLICATIONS

The MD plus system is ideal in many process

applications requiring a closed-loop DC variable speed
drive with an isolated 4-20mA input and output.

Typical applications include:

• Waste water treatment

• Chemical metering processes

• Laboratory mixing equipment

• Industrial auger/mixing equipment

• Polymer injection processes

ASP40-420

The ASP40-420 is also available for applications that
require a closed-loop digital interface with a 4-20mA
input/output and programmable relay outputs, but
already have an existing AC or DC drive in the system.

4-20mA HOOK-UP

P6

3

2

1

6

5

+

4

-

3

+

2

-

1

P3

OPT420 RELAY Output - Common

OPT420 RELAY Output - Normally Open

OPT420 RELAY Output - Normally Closed

- 4-20mA Out (Black)

Auto / Manual Switch

(Closed = Manual)

- 4-20mA In (Black)

5A 250V
Form C
Relay Output

}

(Programmable)

4-20mA OUT

(White)

-

+

4-20mA IN (White)

+

-

CUSTOMER

SUPPLIED

IF NEEDED

+

-

9-36VDC

EXCITATION

SUPPLY

MD50 DRIVE TYPICAL WIRING DIAGRAM

N

OPT420

P1-1

P1-2

P1-3

P1-4

P1-5

P1-6

P1-7

P1-8

P1-9

P1-10

P1-11

P1-12

MD

MASTER

L

-A

+A

COM

COMMON

+5V

S1

S2

NO

C

NC

IN1

-ARM
+ARM

+5VDC

SIGNAL

*

Ground Lug

Jog Input

AC INPUT

85-265VAC

}

AC INPUT

MOTOR

black

red

white

Alarm Output - Normally Open

Alarm Output - Common

Alarm Output - Normally Closed

User Input 1

**INHIBIT

COM (P1-5)

Form C
Relay Output
(Programmable)

}

PICK-UP MOUNTED

TO MOTOR SHAFT

(Mounts on rotating

end shaft with 10-32

tapped hole, 1/2" deep)

* For AC inputs utilizing two hot lines, both inputs should be

SEE

4-20mA HOOK-UP

protected with appropriately sized fuses or circuit breakers.

** P1-8(S2) & P1-12(IN1) user input may be programmed

umber of functions, including (jog, inhibit, etc.)

for a n

METERING PUMP APPLICATION

4-20mA INPUT

PICK-UP FROM
MOTOR OR
FLOW METER

MD50E-420

Item

ValuAuto

Alm1

Alm2Man



CONTROLS

Tach
Error

---

ENTER

4-20mA OUTPUT

MAIN BOARD RELAY OUT

OPT420 RELAY OUT

See your Dart Representative for details or call Dart
Controls at 317-873-5211.

INPUT POWER

AUTO

OFF

MAN

DC Motor

19