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Minimum Depth Indicator - Less Than 2.5” (60mm) of
Space Required Behind the Panel
Stackable Mounting Bracket Included for
Easy Installation
3-1/2 Digit, 0.5” (12.7mm) High LCD Display with
Optional Negative Image, Bright Red Backlighting
Limited Range Display Scaling
Standard Screw Terminals for Easy Installation
Six Current Ranges: 200µA, 2mA, 20mA, 200mA,
2A, 5A
85-250VAC or 9-32VDC Power Supply
2.68”
Mounting Requirements
Insert the Mini-Max through the panel, and then slide the mounting bracket on to the Mini-Max. The mounting bracket allows Mini-Max units to be
stacked side-to-side or top-to-bottom and maintain the DIN standard
panel arrangements in 24mm by 72mm multiples. Panel cutout instructions for stacking multiple units are provided under “Stacking Features.”
Mini-Max M235 Series Digital Panel Meter
Installation and Panel Cutout
Simpson’s Mini-Max Current Indicators provide high quality,
accuracy and reliability in a compact, 60mm deep case.
Units offer 3-1/2 digit, 0.5” (12.7mm) LCD display and are
available with a bright red, negative image backlight option.
All units feature user-selectable decimal point, auto zero and
limited scaling capabilities.
A unique mounting bracket is provided to allow for vertical
or horizontal stacking of multiple indicators. All Mini-Max
units feature a 3/64 DIN, high-impact plastic case. The
standard units have a clear viewing window, and the units
with optional negative image, red backlighting have a red
window.
DC Current
.88"
2.68"
2.36"
0.95"
0.16"
0.13" Max
Panel Thickness
2.84"
.874"
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DISPLAY
Type: 7-segment LCD
Height: 0.5” (12.7mm)
Decimal point: 3 -position programmable
Overrange indication: Most significant digit = “1”
Backlighting: Optional negative image, red back-
lighting
Polarity: Auto with “-” indication, “+” implied
POWER REQUIREMENTS
AC Volt: 85-250VAC @40-440Hz
DC Volt: 9-32VDC
Power Consumption:
85-250VAC: 2.5VA min/4VA max
9-32VDC: 1.5VA min/3VA max
Rated Circuit to Ground Voltage: 750VRMS
ACCURACY @ 25°C
±(0.1% of reading + 1 count)
2A: ±(0.25% of reading + 1 count)
5A: ±(0.50% of reading + 1 count)
ENVIRONMENTAL
Operating Temperature: 0 to 55°C
Storage Temperature: -10 to 60°C
Relative Humidity: 0 to 85% non condensing
@ 40°C
Temperature Coefficient:
(⫾ 0.02% of input ⫾ 0.2 digits)/⬚C
Warmup time: Less than 20 minutes
NOISE REJECTION
NMRR: 60dB, 50/60Hz
CMRR: (w/1K⍀ unbalanced @ 60Hz): 90dB min
ANALOG TO DIGITAL CONVERSION
Technique: Integrating
Rate: 3 samples/second-typical
MECHANICAL
Bezel: 0.95” x 2.84”
(24mm x 72mm)
Depth: 2.36”(60mm)
Panel cutout: 0.88” x 2.68”
(22.2mm x 68mm)
Weight: 3.5oz (99.2g)
Case Material:
94-0,UL rated glass-filled thermoplastic
Specifications
Wiring Display
Display Scaling
Mini-Max indicators have limited range coarse
and fine adjustments for display scaling. There
are no optional connections required for these
to function. The “coarse” calibration R12 will
allow a limited range of scaling values. The
meter can be scaled down to 1/2 the value of
the input or scaled up to 2 times the value of
the input or a maximum reading of 1.999,
which ever is lower. Example: a 2 AMP input
has a maximum reading of 1.999 counts, so
you cant double the 2 AMPs, but you can
make 1 AMP read 1.999. The “fine” calibration
R9 allows for an approximate range of 1% of
the “coarse” calibration. Apply full scale input
to the meter. Adjust R12 to be within 1% of the
desired scaled value, then use R9 to obtain the
final desired result.
Using a screwdriver or thumbnail,
spread tab on each side of case to
unlock top half. Lift rear top half and
slide away from front of meter.
Decimal Point: To select a decimal point, connect the appropriate DP pin (DP1, DP2, or DP3) to the DP COMMON (HOLD). Unused DP inputs
may remain unconnected (open).
Display Hold: Connect HOLD to DP COMMON (HOLD). If this feature is not required, the DP COMMON (HOLD) pin may remain unconnected
(open).
Input Signal: Connect the IN HI and IN LO to the signal to be monitored.
Input Power: Connect power to the L1 and L2 terminals. For AC powered units, L1 and L2 are not polarized.
For 9-32 DC powered units, L1 must be positive with respect to L2.
These instruments are designed for maximum safety to the operator when mounted in a panel according to instruc-
tions. They are not to be used unmounted or for exploratory measurements in unknown circuits.
Voltage Max Input
Range Resolution Drop (unfused)
200µA 100nA 200mV 10mA
2mA 1µA 200mV 40mA
20mA 10µA 200mV 100mA
200mA 100µA 200mV 400mA
2A 1mA 200mV 3A
5A 10mA 50mV 6A
INPUTS: DC Current
NNoottee::
Any physical damage to the meter during
calibration will void the warranty
(Input Signal) IN HI
(Input Signal) IN LO
DP3
DP2
DP1
HOLD
L1 (POS) (Power)
L2 (NEG) (Power)
EX (NEG)
EX (POS)
DP COMMON
(HOLD)
TOP HALF
OF CASE
FRONT
OF METER
LOCKING
TAB
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Stacking Features
The mounting brackets, included with every Mini-Max, can be connected together. Multiple units can be mounted in a single opening, allowing perfect alignment.
To punch one hole for multiple units, be sure to adjust the standard
panel cutout dimensions as shown here; otherwise the meters will not
fit properly in the hole.
Mounting multiple units is quick and easy. Install the first meter (bottom
unit first if stacking vertically). Position the next mounting bracket snugly against the first one, and slide the second meter into place. Repeat
for remaining units.
2.68"
.071"
.88"
Standard cutout
Add to standard
when stacking
.88"
2.68"
Standard cutout
.16"
Add to standard when stacking
Horizontal
Vertical
Vertical
Horizontal
Excitation Output
Excitation output is available in the Mini-Max for powering external
transmitters or transducers. Excitation is available from the EX POS and
EX NEG terminals. This source is isolated from the measurement input
as well as the input power circuits. The voltages available are 12VDC or
24VDC, with a maximum load current of 25 milliamps. This feature eliminates the need to mount an external DC power source for transducers
or sensors used in your application.
Do not exceed an excitation
load current of 25mA!
EX NEG
EX POS
Backlight Option and Decimal Point Selection
Negative image, bright red backlighting is available in the Mini-Max. This illumination allows the
unit to be read in low light areas. Backlighting
power is supplied by the Mini-Max, so no additional external power is required.
Decimal point selection is accomplished by connecting the appropriate DP terminal to the DP
Common terminal.
DP3
DP2
DP1
321 G
DP COMMON
(HOLD)
DP 1
DP 2
DP 3
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Application Example
Ordering Information Safety Symbols
The WARNING sign denotes
a hazard. It calls attention to
a procedure, practice, or the
like, which, if not correctly
performed or adhered to,
could result in personal
injury.
The CAUTION sign denotes
a hazard. It calls attention
to an operating procedure,
practice, or the like, which, if
not correctly adhered to,
could result in damage to or
destruction of part or all of
the instrument.
A company needs to monitor the power
supply voltage and load current of a
12VDC motor.
Voltage: A Mini-Max DC Volt meter, configured for the 20 volt range, is installed in
parallel with the power source. The IN HI
is connected to the positive lead of the
power supply. The IN LO is connected to
the negative lead of the power supply.
Current: A second Mini-Max DC Volt
meter, configured for the 200 millivolt
range, is used with a 100A/50mV shunt
(sold separately) to measure the load current. The meter is first scaled to read
100.0 at 50mV, by applying a 50mV input
to the meter and adjusting R9 and R12
until the display reads 100.0. The meter is
connected to the shunt, and the shunt is
installed in series on the negative leg of the
power supply. The positive lead of the
shunt is connected to the IN HI terminal,
and the negative lead connected to the IN
DC MOTOR
200 mV DC UNIT
20 VDC UNIT
IN HI
IN HI
IN LO
IN LO
POWER SUPPLY
-
+
100 AMP SHUNT
External shunts enable digital panel meters to
indicate higher currents than can be provided
with self-contained internal shunt meters. The
shunt is installed in series with the load and
source. The shunts produce a DCmV drop
which is sent to the display unit. The Mini-Max
can be scaled to display the actual current
between the load and the source. Simpson
offers both portable and switchboard shunts.
Each portable shunt includes 5’ leads.
Accessories
Non Backlight
Negative Image Red
Your Mini-Max Voltage Indicator can be configured by making an entry for each box
Basic Unit Display DPM Power Supply Range Excitation Output
M235
0
2
0
1
0
1
2
21
22
23
24
25
26
3-1/2 Digit Indicator
85-250VAC
9-32VDC
200uA
2mA
20mA
200mA
2A
5A
None
12VDC
24VDC
Note: Models for DC voltage, process, AC TRMS voltage and current, AC frequency and temperature are also available.
LO terminal. The Mini-Max units will indicate the power supply voltage and load
current of the motor.
Portable
Switchboard
Amps Cat. Number
1 06700
5 06703
10 06704
15 06705
25 06707
30 06708
50 06709
75 06711
100 06713
150 06714
200 06715
Switchboard Shunts 50mV
Amps Cat. Number
100 06500
150 06503
200 06504
250 06505
300 06506
400 06507
500 06508
Portable Shunts 50mV
Ordering Information
SIMPSON ELECTRIC COMPANY 520 Simpson Avenue, Lac du Flambeau, WI 54538 • (715) 588-3311 • FAX (715) 588-3326
www.simpsonelectric.com Printed in U.S.A. Part No. 6-116066, Edition 14, 02/09
NNoottee::
Special scaling is available from the factory at the time of ordering.
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