Gems Sensors & Controls DM28 Operating Manual

Introduction

Your Gems Sensors DM28 DC Process is one model in a family of 1/8 DIN units
which offers breakthrough display technology as well as easy-to-program single-line
parameters. Designed to provide instant visual feedback regarding an application’s
key input value, the DM28 not only has a 0.71” high LED display (27% larger than
other 1/8 DIN units), but also the ability to change display color based on process
status (programmable parameter in Operation Mode). Easy programming is made
possible via a help function and a secondary legend display.

This manual will guide you through the installation and wiring of your DM28 unit
with information on proper panel mounting and rear ter minal layout and wiring
instructions. In addition, the instrument’s operation, programming, and
configuration modes are thoroughly explained. The Operation Mode provides day to
day operation and allows editing of preset values. The Program Mode enables the
configuration of various parameters prior to initial operation. These parameters
include those for basic configuration as well as other settable features which will
enhance the functionality
and usability of the device.
The Configuration Mode
allows selection of how
outputs and special
functions are utilized.

Technical Manual

This manual also provides
information on the DM28 DC
Process' alarms; transistor,
relay, and linear outputs;
product specifications; and
ordering and warranty
procedures.

Features

• 0.71” high digit LED display

• Programmable color change display based
on an event

• Programmable help function and secondary
legend display

• High and low alarm outputs

• mA inputs to 50mA, DCV inputs to ±10
Volts and ±100 mV

• Tare function

• Standard outputs: two NPN transistors &
one relay (optional 2nd relay)

• 100 ms sample time with 0.03% accuracy

• CE approved

Index

Installation

Panel Mounting page 2
Wiring page 3

Operation

Front Panel page 4
Operation Mode page 5-6

Programming

Program Mode page 7-10

Configuration

Configuration Mode page 11-14

Appendix A

Specifications page 15

General

Ordering Information page 16
Warranty page 16

182016

DM28-2XXXX
DC Process

INSTALLATION

PANEL MOUNTING

Gems Sensors

OP1
OP2

48mm

82344

100mm

Mounting Grooves

96mm

PGM

RST

92mm +0.5 -0.0

CUTOUT

14 15 16 17 18 19 20

10 11 12

10mm

PANEL

45mm

+0.5 -0.0

SIZE

The instrument can be mounted in a panel with a thickness of up to 6mm. The
cutout(s) should be made based on the recommended panel opening illustrated in the
drawing above.

Insert the unit in the panel through the cutout. Ensure that the
panel gasket is not distorted and the instrument is positioned
squarely against the panel. Slide the mounting clamp into place
on the instrument, as shown to the left, and push it forward until
it is firmly in contact with the rear face of the mounting panel and
the tabs on the bracket arm are seated in the mounting grooves
on the side of the unit.

22

23

24

2

345 678

The electronic components of the instrument can be removed from
the housing after installation without disconnecting the wiring.
To remove the components, grip the side edges of the panel and
pull the instrument forward. Take note of orientation of the unit
for subsequent replacement in the housing.

Bracket Arm

2

INSTALLATION

WIRING

REAR TERMINAL CONNECTIONS

Digital Input

B A

45678

Relay 1

3

22
23

24

2

Relay 2

Linear
Output

Power Supply

+

-

14 15 16 17 18 19 20

10 1 1 12

Control/Digital Inputs

A digital input board, which utilizes Terminals #16 &
#17, can be installed as an option. The input can be
programmed in Configuration Mode to perform one of
two functions:

NPN Out 2

Common

NPN Out 1

Aux. Po wer +

Aux. Power -

V +

mV / mA +

mV / V / mA -

- Tare: When activated, the unit will create an
automatic offset by referencing the currently

Transistor Outputs

Your unit comes standard with 2 NPN outputs which are activated by
each of the alarms. Transistor Output 1, which is tied to Alar m 1, is
on Terminal #7. T ransistor Output 2, which is tied to Alarm 2, is on
Terminal #9. Ter minal #8 serves as the common connection for both
transistor outputs.

Input Power

For an AC powered unit, Terminal #13 serves as the line or Hot side

measured value as the new zero point.

- Security: When activated, the Program Mode
will not be accessible from the front
panel.

connection for AC powered units and as the positive side for DC

Relay Outputs

Your unit comes standard with a relay output which is tied to Alarm

powered units. The neutral side for AC powered units and the
negative side for DC powered units are connected to Terminal #14.

1. Terminal #19 is NC, Ter minal #20 is common, and Terminal #21
is NO. A second relay output tied to the operation of Alarm 2 can be
added as an option at the time of order or later installed in the field.
Terminal #22 is NC, Ter minal #23 is common, and Terminal #24 is
NO.

DC Inputs

Your unit accepts millivolt, Volt, or milliamp DC ranges. Terminal

Linear Output

An option board may be installed that provides a 10 bit linear output
signal relative to the Process Value. Terminal #12 is the positive side
of the connection, and Terminal #10 is the negative side. The default
range of the output is 4-20 mA, but can be changed via the
Configuration Mode to 0-20 mA, 0-10 VDC, 2-10 VDC, 0-5 VDC, or 1-

5 VDC.
#1 is used for mV, V, or mA negative inputs. Terminal #2 is used for
V positive inputs, while Terminal #3 is used for mV or mA positive
inputs.

Meter

Meter

6
2
5
1

6
3
1
5

Exc
Out

Common

Jumper

Jumper

3 -Wire

Voltage

Sensor

+

2 -Wire

­ 4-20 mA

Transmitter

Terminals 4, 11, & 15 are not used.

3

OPERATION

FRONT PANEL

Gems Sensors

Output Indicators

OP1
OP2

82345

PGM

Down Key Scroll Key Program Key Reset Key

Key Functions

Key

Down

Scroll

Program In Operation Mode: Used to move between the process

Reset In Operation Mode: Resets a latched alarm if pressed

Down &

4

Scroll

In Operation Mode: Used in Edit Operation to
decrement the digit highlighted by the Scroll key.

In Program & Config. Modes: Used in Edit Operation to
decrement the digit highlighted by the Scroll key, if the
setting is a numerical value, or present the next in the
series of choices for that parameter .

In All modes: Moves the unit into Edit Operation,
which is indicated by the left most digit flashing.
Successive presses of the key are used to move to the
digit to be edited. Wrap around will occur from least
significant digit to most significant digit.

value display & the presets and to enter an edited
preset value. Holding the key down for 3 seconds will
cause the unit to enter Program Mode if not
disabled by digital input.

In Program Mode: Used to move from one parameter
to the next and enter the edited parameter values.
Holding the key down for 3 seconds will cause the unit
to return to Operation Mode.

In Config. Mode: Used to move from one parameter to
the next and enter the edited parameter values.

while the process value is being viewed. Pressing this
key while viewing the max, min, or elapsed time
value will cause those values to be reset.

In Program & Config. Modes: No function.
In All modes: Will abort an Edit Operation and return

the preset/parameter to its previous value.

Function

H

Secondary Display

Primary Display

RST

Key Functions

Key

Down &
Program

Key

Primary In Operation Mode: Default display is the Process

Secondary In Operation Mode: Provides an alpha or numeric

Output
Indicators

In Config. mode: Holding down both keys for 3 seconds
will cause the unit to return to Operation Mode.

In Operation & Program Modes: Holding down both
keys for 3 seconds will cause the unit to enter to
Config. Mode.

Display Functions

V alue. Can be scrolled using the program key to
display other Operation Mode values. If the "Help"
function is enabled, this display will first show the
parameter description for 3 seconds (example - page 6).

In Program & Config. Modes: Displays the value or
selection for the current parameter . If the "Help"
function is enabled, this display will first show the
parameter description for 3 seconds (example - page 7).

indentification of the value on the primary display.
This display is blank when the Process Value is being
shown.

In Program & Config. Modes: Provides a 1 digit alpha or
numeric character to indicate which parameter value is
being shown on the primary display.

In Operation Mode: Illuminates when Alarm 1 and
or Alarm 2 is active.

In Program & Config. Modes: No function.

Function

Function

OPERATION

OPERATION MODE

CHANGING A PRESET VALUE

Gems Sensors

Default display is the process value.

OP1
OP2

34567

RST

PGM

PGM

Gems Sensors

Proc

PGM

PGM

Gems Sensors

Hi

PGM

RST

H

RST

Pressing the Program Key will cause the

OP1
OP2

display description to appear on the
main display.* If there is no key activity
for 3 seconds, the primary display will
switch back to the process value.

Maximum (High) Value: Displays the

OP1
OP2

maximum process value the unit has
received as an input. The value can be
reset (only while being displayed) by
pressing the Reset Key.

Gems Sensors

AL 1

PGM

PGM

Gems Sensors

AL 2

PGM

PGM

2

1

RST

RST

Alarm 1 Value: Defines the process

OP1
OP2

value at or above which Alarm 1 will
activate if set to Process High Alarm in
Configuration Mode or the process value
at or below which Alarm 1 will be active
if set to Process Low Alarm in
Configuration Mode. The default value
is 100.00

Alarm 2 Value: Defines the process

OP1
OP2

value at or above which Alarm 2 will
activate if set to Process High Alarm in
Configuration Mode or the process value
at or below which Alarm 2 will be active
if set to Process Low Alarm in
Configuration Mode. The default value
is 100.00

Gems Sensors

Lo

Gems Sensors

PGM

PGM

PGM

PGM

PGM

L

RST

EEL ti

RST

Minimum (Low) Value: Displays the

OP1
OP2

minimum process value the unit has
received as an input. The value can be
reset (only while being displayed) by
pressing the Reset Key.

Alarm 1 Elapsed Time: Displays the

OP1
OP2

accumulated amount of time the alarm
1 condition was present. This value will
continue to accumulate until it is reset
by pressing the Reset Key (while the
value is being displayed). The value is
displayed in mm:ss up to 99 min 59
secs., then changes over to mmm.m

Gems Sensors

PGM

Total: Displays the total value based

OP1
OP2

upon integratation of the input signal

ttotAL

RST

using a programmable time base. The
value can be reset (only while being
displayed) by pressing the Reset Key.

* Parameter descriptions will not
appear on the primary display if the
"Help" function has been disabled.

5