Honeywell Home Safety Product HMR4007 User Manual

HMR4007  
SENSOR PRODUCTS  
HMR4007  
Linear Position Sensor  
User’s Guide  
Solid State Electronics Center www.magneticsensors.com (800) 323-8295 Page 1  
 
HMR4007  
SENSOR PRODUCTS  
SPECIFICATIONS  
Characteristics  
Conditions  
Min  
Typ  
Max  
Units  
General  
Accuracy  
0.2  
0.1  
0.1  
0.01  
0.01  
30  
mm  
mm  
mm  
mm  
Hz  
Resolution  
Hysteresis  
Repeatability  
Update Rate  
0.1  
10  
(note 1)  
Standoff  
Distance (gap) between the target  
magnet and the sensor board  
0.1  
5
mm  
Magnetic Field  
Range  
magnetic field at the sensor array  
80(note 1)  
gauss  
mm  
(note 3)  
length  
apparent magnet length at sensor array  
23  
Orientation  
Electrical  
Axial (note 2)  
Input Voltage  
Current  
Unregulated  
6
28  
20  
VDC  
mA  
15  
Digital Interface  
Baud Rate  
Signaling Level  
nonstandard synchronous serial interface  
1000  
3.5  
21,000  
5.0  
Bits / sec.  
VDC  
TTL levels  
( “1” )  
( “0” )  
-0.3  
1.5  
VDC  
Connector  
In-Line 6-Pin Block (0.1” spacing)  
D/A output  
Analog Interface  
Analog Output  
Update Rate  
0
2.5  
VDC  
Hz  
10  
30  
Signaling Level  
TTL levels  
( “1” )  
( “0” )  
3.5  
-0.3  
5.0  
1.5  
VDC  
VDC  
Connector  
Physical  
In-Line 4-Pin Block (0.1” spacing)  
Dimensions  
Circuit Board Assembly  
(including connectors)  
HMR4007  
40.0 x 80.0 x  
12.0  
mm  
grams  
°C  
Weight  
16.5  
Environment  
Temperature  
Operating  
Storage  
-40  
-55  
-
-
+70  
+125  
Note 1: The standoff distance between the sensor board and the target magnet is highly variable. A magnet of sufficient strength,  
however, must be used to maintain a magnetic field strength of 80 gauss (min.) at the sensor array and an apparent  
magnet length of 23 mm.  
Note 2: Sensor boards are factory calibrated in the axial mode using a 27mm cylindrical magnet. Operation in the radial mode  
must be configured by the user.  
Note 3: cf. "Magnet Considerations" (pg. 8)  
Solid State Electronics Center www.magneticsensors.com (800) 323-8295 Page 3  
 
HMR4007  
SENSOR PRODUCTS  
PIN CONFIGURATION  
Pin Number  
Pin Name  
Description  
Digital Interface  
1
RTS  
Data_Out  
Data_In  
CTS  
Serial Clock Output  
Serial Data Output  
Serial Data Input  
Serial Clock Input  
2
3
4
5
6
Power  
GND  
Unregulated Power Input (+6 to +28 VDC) (see note 1)  
Power and Signal Ground  
Analog Interface  
1
Power  
Analog Out  
Position Valid  
GND  
Unregulated Power Input (+6 to +28 VDC) (see note 2)  
0 - 2.5 VDC analog output  
2
3
4
TTL level (0 = position invalid, 1 = position valid)  
Power and Signal Ground  
Jumper Block #1  
2-5  
Note 1  
Note 1  
Analog Output port selected as power source  
3-6  
Serial Communications port selected as power source  
Note 1: The board contains three interface connectors for digital and/or analog communications. Power is supplied to the board  
through any one of these connectors and is selected by jumper block #1. All of the ground connections on all three  
ports are common to the circuit ground and are not affected by the jumper position. Only ONE of the three positions on  
JP1 should be shorted at a time. Shorting more than one may result in excessive power supply currents and board  
damage.  
CIRCUIT DESCRIPTION  
The HMR4007 Linear Position Sensor circuit board includes all of the basic sensors and electronics to provide a  
digital indication of position of a target magnet. The HMR4007 starts with an array of seven Honeywell HMC1501  
single axis magnetoresistive (MR) sensors to determine the field geometry and direction of a target magnet attached  
to the moving part of a device under test. These sensors are supplied power by a constant voltage source, and the  
use of an array of sensors helps to maintain accuracy over temperature and run-out. The sensor outputs are routed  
to a multiplexed Analog to Digital Converter (ADC) integrated circuit. A microcontroller integrated circuit periodically  
queries the multiplexed ADC and performs sensor offset and gain corrections and computes the position of the target  
magnet as a function of the distance of travel along the long axis of the sensor board. The position data, along with  
an error bit, is available thought the serial interface or is present on the Digital to Analog Converter (DAC) output port.  
The serial interface is not needed in order to use the board’s stand-alone analog output. The microcontroller  
also performs the external serial data interface and other housekeeping functions. An onboard EEPROM integrated  
circuit is employed as a nonvolatile storage to retain necessary data and configuration variables for best performance.  
The HMR4007 uses an on-board low drop out (LDO) +5 volt regulator so that a regulated +5 volt power supply or an  
unregulated power supply in the range of +6VDC to +28VDC can be used. The power is supplied to the board  
through one of the three user ports being (serial, analog, or USB) and a jumper is used to select which port is the  
power source. Only one jumper should be in place at any one time as the board does not have over current  
protection and use of more than one jumper can result in excessive power supply currents and board damage.  
Solid State Electronics Center www.magneticsensors.com (800) 323-8295 Page 4  
 
HMR4007  
SENSOR PRODUCTS  
PHYSICAL CHARACTERISTICS  
The circuit board for the HMR4007 Linear Position Sensor is approximately 340mm by 80mm. A 6-pin right angle  
connector (J1) and two 4-pin connectors (J2, J3) protrude from the back of the board for user connections.  
Components on the top-side have a maximum height of 12mm. Figure 1 shows a typical circuit board with  
dimensions.  
PARTS PLACEMENT  
x
x
1
x
x
x
x
3
Not used  
leave all OPEN  
2
JP1  
Where 1 = J3 (USB)  
2 = J2 (Analog output)  
3 = J1 (digital communications) - shown above  
Sensed axis  
4-40NF mounting holes  
(connected to ground plane)  
4 3 2 1  
6 5 4 3 2 1  
USB port  
not used  
PC (parallel port)  
Sensor Board  
Sensor Board  
LPT bit  
LPT pin  
J1 pin  
uP bit  
RA3  
RA2  
RA1  
RA0  
Vcc  
function  
Tx_CLK  
Tx  
color  
(gray)  
(yellow )  
(blue)  
J2 pin  
1
2
uP pin  
Vcc  
function  
S3  
S4  
D1  
D0  
-
15  
13  
3
<
<
1
2
3
4
5
6
power input (5-28VDC)  
status (TTL output)  
RA4  
Logic 0 = output not valid  
Logic 1 = output valid  
>
Rx  
2
>
Rx_CLK  
+ 5-28 VDC  
pow er gnd  
(w hite)  
(red)  
3
4
D/A Output  
GND  
analog output (0 - 2.25V)  
power ground  
-
< >  
< >  
-
19  
GND  
(black)  
Sx = status (LPT port base address + 1, Bit x)  
Dx = data (LPT port base address + 0, Bit x)  
Figure 1 – Sensor board layout and connector pin designations  
MATING PARTS  
Connectors J1, J2, and J3 mate with GC/Waldom C-Gridcrimp-style shells and terminals. Polarized shells (with a  
locking tab) or unpolarized shells are available. The applicable GC/Waldom part numbers are:  
Connector  
pins  
Polarized shell  
50-57-9406  
50-57-9404  
50-57-9404  
Unpolarized shell  
50-57-9006  
Crimp terminals  
16-02-0097  
J1  
J2  
J3  
6
4
4
50-57-9004  
50-57-9004  
16-02-0097  
16-02-0097  
Solid State Electronics Center www.magneticsensors.com (800) 323-8295 Page 5  
 
HMR4007  
SENSOR PRODUCTS  
APPLICATION NOTES  
USING THE HMR4007 AS A STAND ALONE SENSOR  
Introduction  
The HMR4007 can be used as a stand-alone sensor without the need for any digital communications. The board is  
configured at the factory to provide a 0-2.5 VDC analog output (axial magnet) and status signal that represents the  
position of the magnet along the long axis of the device. All power and signals are available on connector J2.  
Connector J2 General Description  
When used in a stand-along mode, only connector J2 needs to be used. Connector J2 is a 4-pin socket header that is  
used to supply power (pin 1), ground (pin 4), analog position (pin 3), and status (pin 2). When power is supplied to  
the board though J2, a jumper must be placed on pins 2-5 (center pair) in jumper block JP2. The power supply can  
be regulated 5VDC or unregulated 6-28VDC. If connector J2 is used in combination with the communications port,  
only ONE of the ports should be used to supply power to the board.  
Analog Outputs  
The analog output (J2, pin 3) represents the position of the magnet along the long axis of the sensor board as seen in  
Figure 2 below. In the given example, the center of the magnet lies between sensors 3 and 4. The resulting output  
voltage is 1.20 volts which corresponds to a position of 33.4 mm.  
69.6  
33.4 m m  
N
34.8  
1.20 vdc  
S
0
0
1.25  
2.50  
O utput (volts, D C )  
Figure 2. Position sensing example.  
An effort should be made to keep the angle of the magnet with respect to the sensor board reasonably constant along  
the length of travel. The sensor, however, is quite tolerant to changes in distance (gap) between the sensor and  
magnet along the length of travel.  
Status Pin  
Pin 2 (on port J2) is a TTL logic-level status output bit. This pin will be logic high (+5VDC) whenever the position  
output is valid. Logic level low (ground) indicates that the sensor cannot calculate a magnet position. The most likely  
causes of a position error signal are:  
1. The magnet is beyond the sensed range of the device.  
2. The magnet is too short or too weak for the sensors to track.  
3. The gap between the sensor and magnet is too large.  
4. The magnet is not present.  
Solid State Electronics Center www.magneticsensors.com (800) 323-8295 Page 6  
 
HMR4007  
SENSOR PRODUCTS  
USING THE HMR4007 IN DIGITAL COMMUNICATIONS MODE  
Introduction  
The HMR4007 is capable of communicating with a higher-level system through a proprietary communications port  
(J1). This port uses a bit-clocked serial protocol for higher speed and higher data integrity than standard serial  
protocols. Signal levels are standard TTL compatible. For convenience, a windows-based DLL (dynamic link library)  
and sample Visual Basic demonstration program are available from Honeywell that communicates with the sensor  
through a PC's parallel port. Interested developers should contact their Honeywell representatives or the factory for  
details of the communications protocol and command structure. The communications port can be used independently  
or in combination with the analog output described earlier. When used in combination with the analog port, only ONE  
port should be used to supply power to the board. Sensor configuration, such as changing the magnet mode from  
axial to radial, is available only through the communications port and DDL calls are supplied to support these basic  
functions.  
Connector J1 General Description  
J1 is a 6-pin header which is wired to a PC parallel port for digital communications with the Honeywell demonstration  
DLL software (or other user application) using the following connections:  
PC (parallel port)  
Sensor Board  
LPT pin  
data  
direction  
<--  
J1 pin  
function  
color  
15  
13  
3
2
-
1
2
3
4
5
6
RTS  
Data_Out  
Data_In  
CTS  
+5-28 VDC  
power gnd  
(gray)  
(yellow)  
(blue)  
(white)  
(red)  
<--  
-->  
-->  
<>  
<>  
19  
(black)  
Demonstration Software  
Two programs are included with this board to demonstrate its operation.  
HMR4007.dll is a dynamic link library that performs low level communications between the host PC's parallel port  
and the sensor board to query the current, measured position and support operating mode changes. Several  
functions are visible to the user using the following Visual Basic header formats:  
Declare Function InitPort Lib "HMR4007.dll" (ByVal ADD As Integer, ByVal TOut As Long) As Integer  
Declare Function CurrentPosition Lib "HMR4007.dll" () As Integer  
Declare Function SetAxialMode Lib "HMR4007.dll" () As Integer  
Declare Function SetRadialMode Lib "HMR4007.dll" () As Integer  
Declare Function EnableDAC Lib "HMR4007.dll" () As Integer  
Declare Function DisableDAC Lib "HMR4007.dll" () As Integer  
The first function, "InitPort", is used to setup the PC's parallel port base address (default is 0x378) and timeout value.  
This function must be called before any calls to the operating functions.  
The port base address (ADD) is the address of the computer's parallel (printer) adapter and used by the software  
as a base address to send and receive data to the sensor card through the parallel port adapter. The value is  
passed as a 16-bit integer. Setting this value to -1 re-initializes the port with the previous value (or default value)  
retained.  
The timeout value (Tout) is used as an internal loop counter to return to the calling program after a fixed time if  
for some reason the sensor board fails to respond. A value of 10,000 is the default and works well on a 100MHz  
Pentium-class machine. Higher values will be needed for faster machines. The parameter is passed as a 32-bit  
long integer. Passing a value of -1 sets the value to the previous (or default) value.  
The function returns a 16-bit integer "0" to indicate that the port is active.  
Solid State Electronics Center www.magneticsensors.com (800) 323-8295 Page 7  
 
HMR4007  
SENSOR PRODUCTS  
The second function, "CurrentPosition", is used to query the current position of the magnet. The following 16-bit  
integer values are returned:  
0-1024  
-1, -2  
normal position response where 1024 represents full scale response.  
communications failure. The sensor failed to respond to the PC quickly enough. This is  
usually caused by improper wiring, improper power settings, a timeout value too small for  
the PC speed, or the DLL not being initialized before attempting to get the position.  
position error. The sensor communicated correctly, but the sensor card was not able to  
calculate a valid position. A position error is usually caused by the magnet being off the end  
of the board or not present.  
-3  
The functions "SetAxialMode" and "SetRadialMode" are used to configure the sensor to use magnets in either the  
axial mode or radial (see the introduction for a description of axial and radial modes). The sensor is shipped with the  
axial mode selected. Once set into an operating mode, that mode is retained in nonvolatile RAM.  
The functions "EnableDAC" and "DisableDAC" are used to enable and disable the digital to analog (DAC) output on  
port J2. The sensor is shipped with the DAC enabled. Once set into an operating mode, that mode is retained in  
nonvolatile RAM.  
HMR4007.exe: This is a simple Visual Basic 5.0 executable that demonstrates the use of the DLL and shows a  
simple graphical display of the current position. Source code for the program is available and can be modified as  
desired. The position window will turn yellow in the event of a communications failure, or turn red in the event of a  
position error.  
MAGNET CONSIDERATIONS  
The choice of magnet to be used with the HMR4007 is critical to its accuracy. Because a magnet's field extends  
beyond the boundaries of the material, a magnet has two dimensions to consider: its physical (material) length and its  
apparent (magnetic) length. The heart of the HMR4007 is Honeywell's HMR1501 magnetoresistive (MR) sensor that  
responds to the angle between the chips' sensitive axis and the magnetic field. The HMR1501 has a maximum  
response when this angle is +/-45 degrees. We can, therefore, define the magnet's apparent length as the distance  
between the +45 and -45 degree points at the gap distance.  
As the gap between the magnet and the sensor array increases, the  
apparent length of the magnet increases as well. A general rule of  
HMR1501  
response  
= f(4)  
Bx  
thumb for a cylindrical bar magnet is that the apparent length will  
increase by the amount of the gap. A twenty-five millimeter long  
B
4
magnet for example will appear to be thirty-five millimeters long at a  
gap of 10 millimeters. Since magnetic fields are highly nonlinear and  
subject to the exact geometry and properties of the material, this is only  
a general guide.  
The HMR4007 uses three sensors in its array at all times in order to  
calculate position. It automatically selects the sensors closest to the  
magnet for this purpose. The apparent magnet length must, therefore  
be greater than he spacing between three sensors, and this distance is  
23.2mm for the HMR4007.  
N
S
physical  
length  
apparent  
length  
The disadvantage of increasing the gap between the sensor and  
magnet in order to increase its apparent length is that a magnet's field  
strength decreases exponentially with gap. In order to maintain the MR  
sensor's response the magnetic field at the sensor must be greater  
than 35 gauss. Unless extremely strong rare earth magnets are  
economically feasible or a large gap is required because of restrictions  
on where the magnet and array can be mounted, it is usually better to  
keep the gap to a minimum and use a longer magnet.  
gap  
Figure 3. Magnet apparent length  
900301 01-03 Rev. A  
Solid State Electronics Center www.magneticsensors.com (800) 323-8295 Page 8  
 

Graco MP3 Player Accessories 3A2079A User Manual
Grizzly Planer G0634Z User Manual
Groupe SEB USA T FAL Gas Grill CB6080 User Manual
Hamilton Beach Blender HBB250S User Manual
Harbor Freight Tools Noise Reduction Machine 45146 User Manual
Hearth and Home Technologies Indoor Fireplace Columbia Bay User Manual
Heat Glo LifeStyle Indoor Fireplace 6000TV OAK User Manual
HP Hewlett Packard Personal Computer C7J85US#ABA User Manual
HP Hewlett Packard Personal Computer t5545 User Manual
Husky Battery Charger HSK1084HD User Manual