1.0 Technical Specifications

1.1 Electrical 

Operating Voltage Range: +/– 25% of nominal voltage.

Operating Current Range: Values reflect keyswitch in “on” position.

1.2 Mechanical

Display: LCD with 10-segment bar and 5 digit numeric (5mm high).

Hour Meter Range & Resolution: 9,999.9 Maintenance Hours;

 99,999 Total Hours

Hardware: Mounting Bracket

Panel Cutout: 52 mm / 2 1/16” diameter

1.3 Environmental

Shock: SAE J 1378 Amplitude 

 44-55 g, half sine, 9-13 ms duration. 

Vibration: SAE J 1378 Double amplitude of 1.53mm with frequency sweep

 for 10-80-10 Hz (20 g max) at 1 minute intervals.

Operating Temp.: –40 ̊C to +85 ̊C.

Storage Temp.: –50 ̊C to +90 ̊C.

Humidity: 95% RH (non-condensing).

IP Rating: 65 Front & Rear with AMP connector installed.

 65 Front, 40 Rear with Molex connector installed.

2.0 Installation

2.1 Terminal Assignments

2.2 Typical Wiring Diagrams 

See wiring schematic drawings on reverse side of page.

2.3 Mounting

Caution!

Bracket is placed over gauge in reverse fashion for ease of shipping. Bracket 

has been designed to remain secured to the gauge upon proper installation. 

Once installed correctly, attempts to remove bracket from gauge may result in 

damage to the bracket.

See complete drawing with notes on reverse side of page.

Curtis enGage® II instruments are mounted in a 52mm round cutout. Serrations 

on the barrel of the gauge, combined with the mounting bracket provided, 

insure fast and trouble free installation. To insure proper installation, the 2 

locking tabs on either side of the inner diameter of the bracket should aligned 

with the serrations on the barrel of the gauge (see drawing above). Next, slide 

the bracket over the barrel of the gauge and press it firmly against back of 

panel. You should hear the tab sliding over the serrations.

2.4 Interconnect

Curtis enGage® II mates with either an 8-pin Molex connector (Molex pins 

P/N 39-00-0039 FOR #18-24 AWG P/N 39-01-2085) or an 8-pin AMP connector 

(AMP pins P/N 770904-X FOR #18-24 AWG P/N 794821-1). A preassembled 

mating connector kit (Curtis P/N 15369002=Molex , Curtis P/N 17633308-

03=AMP) with crimp-connect terminated wires (approx. 127mm in length) 

is also available.

2.5 Product Identification

2.5.1 Programmable Vs. Factory Set Instruments

Curtis enGage® II gauges are

available with or without front panel 

buttons. Gauges without buttons are 

factory set and cannot be adjusted in 

the field. Gauges with buttons have 

field adjustable parameters and can be 

programmed per section 2.6.

2.5.2 enGage® II & Multifunction Design

Curtis enGage® II products can be configured in a variety of ways to maximize 

customer value and efficiency. Because of this feature, the instruction manual 

covers a broad spectrum of products. Please note that some sections of the 

instructions may refer to functions not included with your instrument.

2.6 Configuring Your Gauge

Access to these operations is sequential in this order. Adjustments of the 

following functions can be performed in the Configuration Mode:

1. Time-of-Day Clock

2. Battery Discharge Indicator profiles

3. Maintenance interval 

4. Settable hour meter 

During configuration, the right button is used to increment. The left 

button is used to: 

1. Enter a selection; 

2. Advance to the next configurable item.

If no change is desired to a specific gauge function, continue to press the left 

button until the next desired function is reached.

The time-of-day clock is entered by setting the hours digits between 01 and 12, 

then “minutes” digits between “00” and “59”.

The profile of the BDI is settable with the front panel buttons. The Discharge 

Full profile (when the gauge will begin calculating ‘discharge’) is adjustable from 

1.80 through 2.30 volts per cell (VPC) in 0.01 VPC increments. The Discharge 

Empty profile (when the gauge will indicate ‘empty’) is adjustable from 1.50 

through 2.20 VPC in 0.01 VPC increments.

The maintenance interval (when the gauge signals that maintenance is due) is 

configurable and should be set after the initial installation. The interval can be 

set between 1 and 9,999 hours in 1 hour increments.

The settable hour meter can be set to any value between 0 and 99,999 hours. 

When the gauge is operational, the total hour meter will begin from this value.

Configuration Notes:

The gauge remains in configuration mode for 30 seconds without input from 

the user.

When configuring each function (time-of-day, maintenance interval, etc.), you 

must enter in all data for that function for it to be saved. If incomplete data 

is entered for a function and the programming mode is timed out (after 30 

seconds of no input received by the gauge), the gauge will revert back to what 

was previously stored for that item.

If you interrupt the data entry process in the Configuration Mode, the gauge 

saves data in those sections already completed. To complete configuration, 

re-enter configuration mode (2.6.1) and simply toggle past the completed 

sections and resume where you left off.

2.6.1 Entering Configuration Mode

1. Apply main power (9-60VDC) to V+, V–.

2. Apply V+ (9-60 VDC) to Keyswitch Input. 

3. Apply V+ (9-60 VDC) to Set-up Enable.

4. Press and hold the left button on the front panel until the entire

display flashes and then release.

2.6.2 Setting the Time-of-Day Clock

The display will flash the two “Hours” digits. Press the right

 button to increment by one hour, or hold the button to increment 

continuously. When the desired number of hours is reached, 

press the left button once. The display will flash the two 

“Minutes” digits. Press the right button to increment by one minute or hold 

the button to increment continuously. When the desired number of minutes is 

reached, press the left button once.

2.6.3 Setting the Battery Indicator Profiles

The display will flash the three digits of the discharge full profile 

(factory setting is 2.09 VPC). Press the right button to 

increment by 0.01 VPC or hold the button to increment

continuously. When the display reaches 2.30 it will automatically 

restart at 1.80 VPC. When the desired reset profile setting is reached, press the 

left button once.

The display will flash the three digits of the discharge empty 

profile (factory setting is 1.73 VPC). Press the right button 

to increment by 0.01 VPC or hold the button to increment 

continuously. When the display reaches full it will automatically 

restart at 1.50 VPC. When the desired reset profile setting is reached, press the 

left button once.

2.6.4 Setting the Maintenance Interval

The display will flash the left digit (thousands of hours). Press 

the right button to increment by one or hold the button to 

increment continuously. When the desired number is reached, 

press the left button once to proceed to the next digit. 

Repeat this process for all 4 digits.

2.6.5 Setting the Total Hour Meter

The display will flash the left digit (tens of thousands of hours). 

Press the right button to increment by one or hold the button 

to increment continuously. When the desired number is reached, 

press the left button once to proceed to the next digit. 

Repeat this process for all 5 digits.

2.6.6 Exiting Configuration Mode

The configuration mode can be exited in three ways:

1. Press and hold the left button for three seconds.

2. Leave buttons untouched for 30 seconds.

3. Press the left button after selecting the last (right) digit of the last 

function available.

3.0 Operation

When the main power (9-60 VDC) is applied to V+ and V–, a 

power-up sequence is initiated. All display segments are illuminated 

for one second. The display is then turned off until the keyswitch 

is activated.

3.1 Button Use During Normal Operation

3.1.1 Toggling Display Functions

Press the left button to sequentially toggle between the three numeric 

gauge functions (time-of-day clock, maintenance hours, total hours).

The following procedures (3.1.2 and 3.1.3) can be done without V+ applied to 

Setup Enable pin. Press and hold the left button on the front panel until the 

entire display flashes and then release.

3.1.2 Setting/Changing the Time-of-Day Clock

See Section 2.6.2. 

3.1.3 Resetting the Maintenance Hour Meter

Press the left button until the maintenance hour meter function is 

displayed (the wrench icon will be illuminated). Press and hold both the 

right button and the left button until the display flashes and the 

maintenance hour meter is reset to zero. This can be performed at any time, 

independent of the actual maintenance status.

3.2 Auto-range

Curtis enGage® II will automatically recognize battery voltage based on the 

status of the auto-range input pin.

3.3 Output and Warning LED

KEY: RMB = Right Most LCD Bar / LMB = Left Most LCD Bar

3.4 LCD Icons

Curtis enGage® II contains a number of icons to assist the user:

Hourglass Icon: Turned on (not blinking) to indicate that an hour meter is 

displayed in the numeric display. Flashes to indicate hour meter accumulation.

Wrench Icon: Turned on (not blinking) to indicate that the maintenance hour 

meter is displayed in the numeric display. Flashes when the maintenance 

interval is reached.

Colon: Flashes to indicate that the time-of-day clock is being displayed in 

the numeric display and that time is counting-up.

Decimal Point: To indicate 1/10 of an hour on the maintenance hour meter

Fuel or Battery Icon: Turned on (not flashing) depending on which function 

the gauge is programmed to monitor. It flashes when a low condition is 

detected.

Percent: Indicates remaining percentage of interval or level.

3.5 Resetting BDI

OCR—Open Circuit Reset: The BDI will reset when gauge is disconnected from 

discharged battery and reconnected to a fully charged battery.

CTR—Charge Tracking Reset: Battery state-of-charge will be tracked by gauge 

during charging period(s). 

4.0 Troubleshooting

BDI Function

Sender Function

Maintenance Function

5.0 Maintenance

The enGage® 3000 Series is not serviceable. 

Safety Instructions

• This instrument was manufactured and tested according to the applicable 

technical standards. It complies with all the safety regulations as shipped from 

the factory.

• Installation and startup must be performed by skilled personnel.

• Failure to install and operate the unit in accordance with these instructions 

may result in damage or injury.

• If safe operation of the instrument can no longer be ensured, stop and secure 

it against accidental operation.

• If instrument failure or malfunction may cause personal injury or material 

damage, use additional safety measures such as limit switches, guards, etc.

• Read the Operating Instructions carefully before startup.

• Note the safety instructions marked with this warning symbol 

in this manual.

Warranty

Curtis Instruments’ products and/or components are guaranteed against 

defects in workmanship and material for a period of two years, or as defined 

in the individual product literature, from date of shipment from our factory, 

when applied in a proper application within specified ratings. This guarantee 

is limited to repair or replacement F.O.B. our factory. There is no further 

warranty or implied representation, guarantee, promise or agreement as to 

any Curtis Instruments product and/or component. Curtis Instruments, Inc., 

cannot assume responsibility or accept invoices for unauthorized repairs to 

its products and/or components, even though defective. In no case will Curtis 

Instruments’ responsibility extend to products, components or equipment not of 

its manufacture. Under no circumstances shall Curtis Instruments, Inc., be liable 

for any special or consequential damages or loss of profits or other damages. 

Returned goods will not be accepted unless identified by a Curtis Return 

Material Authorization (RMA).

All specifications are subject to change without notice.

0 1

0 1 0 1 0 1

0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1

53034 Rev E 6/10

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

0 1

0 1 0 1 0 1

3000 Series Instructions ® Read Instructions Carefully!

CURTIS INSTRUMENTS, INC. 200 Kisco Avenue, Mt. Kisco, NY 10549 Tel. (914) 666-2971 www.curtisinstruments.com 

Without buttons With buttons

Gauge

Operating Voltage 

(VDC) Nominal (mA) Max (mA)

12 VDC 12 19 35

12–48 VDC 12 14 20

24 16 20

36 16 20

48 17 20

Function LED Activated FET Activated

Fuel LMB LMB

Temp RMB RMB

Pressure LMB & RMB LMB & RMB

Voltage 2nd LMB & RMB 2nd LMB & RMB

Tach RMB RMB

BDI LMB LMB

Maintenance Due LMB LMB

Problem Possible Cause

No Display Terminals not connected.

Improper voltage.

Stays at FULL Instrument voltage does not match 

battery voltage.

V+ connected to wrong terminal.

Will Not Reset Instrument voltage does not match 

battery voltage. 

Battery not fully charged. 

Battery may be defective

Resets without Charging Battery Not connected directly to battery 

terminal

EMPTY Too Soon V+ connected to wrong terminal.

Instrument voltage does not match 

battery voltage.

Terminals not directly connected to 

battery.

Will Not / Cannot Configure Procedure in section 2.6.1 not being 

followed.

No power to Setup Enable pin.

Problem Possible Cause

No Display Terminals not connected.

Improper voltage.

Stays at FULL V+ connected to wrong terminal.

Sender or sender connection problems.

EMPTY Too Soon V+ connected to wrong terminal.

Sender or sender connection problems

Problem Possible Cause

Will not Reset Section 3.1.3 procedure not being 

followed.

Molex Pin # Description AMP Pin #

8 V(+) 4

Supply Voltage Positive Terminal. For BDI applications, 

connection should be made as close to battery positive 

as possible.

4 V(–) 8

Supply Voltage Negative Terminal For BDI 

applications, connection should be made as close to 

battery as possible.

2 Keyswitch (+) 6

When V+ is applied, the keyswitch turns on the gauge 

display. For BDI applications, monitoring continues 

when keyswitch is turned off.

6 Setup Enable (+) 2

When V+ is applied, the gauge can be programmed via 

the front panel buttons if so equipped (see section 2.6).

7 Hour Meter Enable (+) 3

When V+ is applied, accumulation of time occurs with 

keyswitch turned on.

5 Input A 1

Input for a voltage based sender OR auto ranging pin 

in BDI applications. See schematic diagrams for AMP 

and Molex connectors.

1 Input B 5

Input for resistance based senders.

3 FET Output 7

MOSFET (0.5A) open drain type internally tied to V(–).
DO NOT CONNECT WHEN INSTALLING GAUGE

USED FOR DEVICE CONFIGURATION

8

4

5

1

LABEL

LABEL

SEAL

MOUNTING BRACKET

51.5 MAX

46.0 MAX

53.6 MAX

58.5

6.3

MEMBRANE SWITCH USED

FOR FUNCTIONALITY SETUP

OF GAUGE

60.0

LOGO AREA/SCALES

AS REQUIRED

4.0 This unit is designed for a mounting panel thickness of 0.8mm - 6.4mm.

 Cover, Overlay & Mounting Bracket- Polycarbonate.

3.0 Material: Case- Polycarbonate; Lens- clear Polymethylmethacrylat (pmma);

 Rating 94V-0, pins P/N 39-00-0039 for #18-24 AWG

1.0 Mating Connector: 8-pin Molex P/N 39-01-2085 with ULNOTES:

2.0 52mm meters are provided in a standard round package for

 mounting in a 52mm DIA dash panel hole. See detail for panel cutout with key.

5.0 Environmental protection: Front- IP-65; Rear- IP-40.

6.0 Weight: 0.095 kg max, including mounting bracket.

SUPPLY

4 3 2 1

8 7 6 5

HOUR METER

ENABLE

SETUP

ENABLE 

RESISTANCE BASED SENDER 

+

-

SUPPLY

AUTO-RANGE SWITCH OPEN = 24 or 48 CLOSED = 12 or 36

+

-

SUPPLY

KEYSWITCH

+

-

4 3 2 1

8 7 6 5

4 3 2 1

8 7 6 5

V+

VPIN 7 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 7 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 7 = 0.5A FET

LOAD*

LOAD*

LOAD*

SUPPLY

4 3 2 1

8 7 6 5

RESISTANCE BASED SENDER 

+

-

SUPPLY

4 3 2 1

8 7 6 5

AUTO-RANGE SWITCH OPEN = 24 or 48 CLOSED = 12 or 36

+

-

SUPPLY

4 3 2 1

8 7 6 5

+

-

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 3 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 3 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 3 = 0.5A FET

LOAD*

LOAD*

LOAD*

SUPPLY

4 3 2 1

8 7 6 5

HOUR METER

ENABLE

SETUP

ENABLE 

RESISTANCE BASED SENDER 

+

-

SUPPLY

AUTO-RANGE SWITCH OPEN = 24 or 48 CLOSED = 12 or 36

+

-

SUPPLY

KEYSWITCH

+

-

4 3 2 1

8 7 6 5

4 3 2 1

8 7 6 5

V+

VPIN 7 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 7 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 7 = 0.5A FET

LOAD*

LOAD*

LOAD*

SUPPLY

4 3 2 1

8 7 6 5

RESISTANCE BASED SENDER 

+

-

SUPPLY

4 3 2 1

8 7 6 5

AUTO-RANGE SWITCH OPEN = 24 or 48 CLOSED = 12 or 36

+

-

SUPPLY

4 3 2 1

8 7 6 5

+

-

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 3 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 3 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 3 = 0.5A FET

LOAD*

LOAD*

LOAD*

SUPPLY

4 3 2 1

8 7 6 5

HOUR METER

ENABLE

SETUP

ENABLE 

RESISTANCE BASED SENDER 

+

-

SUPPLY

AUTO-RANGE SWITCH OPEN = 24 or 48 CLOSED = 12 or 36

+

-

SUPPLY

KEYSWITCH

+

-

4 3 2 1

8 7 6 5

4 3 2 1

8 7 6 5

V+

VPIN 7 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 7 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 7 = 0.5A FET

LOAD*

LOAD*

LOAD*

SUPPLY

4 3 2 1

8 7 6 5

RESISTANCE BASED SENDER 

+

-

SUPPLY

4 3 2 1

8 7 6 5

AUTO-RANGE SWITCH OPEN = 24 or 48 CLOSED = 12 or 36

+

-

SUPPLY

4 3 2 1

8 7 6 5

+

-

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 3 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 3 = 0.5A FET

HOUR METER

ENABLE

SETUP

ENABLE KEYSWITCH

V+

VPIN 3 = 0.5A FET

LOAD*

LOAD*

LOAD*

Molex Connector AMP Connector

Resistive based sender input (i.e. temp, fuel and pressure).

BDI (with auto-range switch)

Voltmeter

2.2 Typical Wiring Diagrams

2.3 Mounting/Dimension Drawing

LOCKING TAB MUST ALIGN WITH LOCKING SERRATIONS

LOCKING TAB

LOCKING SERRATIONS

*Use of output FET driver requires installation of suppression diodes across all inductive loads.

Information is for standard design units only. Customers should review 

specific diagrams for custom units.

Information is for standard design units only. Customers should review 

specific diagrams for custom units.