Difference between revisions of "MASTECH MAS345"
Jump to navigation
Jump to search
Uwe Hermann (talk | contribs) m |
Uwe Hermann (talk | contribs) m |
||
Line 1: | Line 1: | ||
{{Infobox multimeter | {{Infobox multimeter | ||
| image | | image = [[File:Mastech_mas345_device_front.png|180px]] | ||
| name | | name = MASTECH MAS345 | ||
| status | | status = planned | ||
| source_code_dir | | source_code_dir = | ||
| counts | | counts = 4000 | ||
| categories | | categories = CAT II | ||
| connectivity | | connectivity = [[Device_cables#MASTECH_MAS34X_cable|RS232]] | ||
| measurements | | measurements = voltage, current, resistance, capacitance, temperature, hFE, diode, continuity | ||
| features | | features = autorange, data hold, bargraph, backlight | ||
| website | | website = [http://web.archive.org/web/20080305031323/http://www.p-mastech.com/products/04_dm/mas345.html p-mastech.com] | ||
}} | }} | ||
The | The '''MASTECH MAS345''' is a 4000 counts, CAT II handheld digital multimeter with RS232 connectivity. | ||
It is also sold under the names [http://www.circuitspecialists.com/csi345.html Circuit Specialists CSI345]<sup>1</sup>, [http://web.archive.org/web/20070224223043/http://www.globalspecialties.com/pro70.html Global Specialties Pro-70], [http://www.xlsmess.de/html/mcvoice_-_m-345pro.html McVoice M-345pro], [http://www.sinometer.com/jpg/MAS345.jpg Sinometer MAS345]. and [http://www.velleman.eu/products/view/?country=ot&lang=de&id=341708 Velleman DVM345DI]. | It is also sold under the names [http://www.circuitspecialists.com/csi345.html Circuit Specialists CSI345]<sup>1</sup>, [http://web.archive.org/web/20070224223043/http://www.globalspecialties.com/pro70.html Global Specialties Pro-70], [http://www.xlsmess.de/html/mcvoice_-_m-345pro.html McVoice M-345pro], [http://www.sinometer.com/jpg/MAS345.jpg Sinometer MAS345]. and [http://www.velleman.eu/products/view/?country=ot&lang=de&id=341708 Velleman DVM345DI]. |
Revision as of 09:41, 28 November 2012
Status | planned |
---|---|
Counts | 4000 |
IEC 61010-1 | CAT II |
Connectivity | RS232 |
Measurements | voltage, current, resistance, capacitance, temperature, hFE, diode, continuity |
Features | autorange, data hold, bargraph, backlight |
Website | p-mastech.com |
The MASTECH MAS345 is a 4000 counts, CAT II handheld digital multimeter with RS232 connectivity.
It is also sold under the names Circuit Specialists CSI3451, Global Specialties Pro-70, McVoice M-345pro, Sinometer MAS345. and Velleman DVM345DI.
1 The software shipped by Circuit Specialists is MasView 1.1.
Hardware
Multimeter:
- Main chip: MASTECH Japan M343-01 F0951D174 (80 pins, 16 + 16 + 24 + 24)
- 14-stage binary counter/oscillator: ST 74HC4060 (datasheet) (marking: "ST 74HC4060 N00U732")
- Precision perational amplifier: Texas Instruments OP07C (datasheet) (marking: "12AL9JM 0P07CP")
- CMOS multifunctional time base circuit: Green Sea Technology GC7555AP (datasheet, English translation) (marking: "GC7555AP AA7057HS")
- This is an NE555 compatible chip, apparently.
- General-purpose photocoupler: Sharp PC817 (datasheet) (marking: "B > B5 PC817 Sharp")
- "B": model = PC817X2J000F/PC817XF2J00F, ">": China factory, "B5": date code == May 1991
- General-purpose photocoupler: Sharp PC817 (datasheet) (marking: "B > B6 PC817 Sharp")
- "B": model = PC817X2J000F/PC817XF2J00F, ">": China factory, "B6": date code == June 1991
- Crystal: ca. 32kHz
- Fuse: 15A/250V (6x30mm) (for the 10A jack; interestingly the PCB silkscreen says "20A" for that jack)
RS232 cable:
Photos
Multimeter:
RS232 cable:
See Device cables#MASTECH_MAS34X_cable.
Protocol
The protocol is (partially) documented in the vendor software's "Help" window (seems to apply to MAS343, MAS344, and MAS345; the M9803R protocol is different).
- Serial port settings: 600 baud, 7n2, RTS low, DTR high
- Every time the host sends a (any?) character to the DMM (the vendor software sends D/0x44), it returns 14 ASCII bytes containing the measurement value and so on. The documentation states that a request interval of >= 1 second is "required for stable measuring data from meter".
Packet format:
Byte(s) | Description |
---|---|
1-2 | Measuring mode (DC, AC, OH, CA, TE, DI, ...) |
3 | Always a space (?) |
4 | Sign ('-' or ' ', i.e. a minus or a space) |
5-9 | Decimal point and current measurement value (Examples: 10.00, 0L, 3.999) |
10-13 | Unit (Examples: V, mV, A, mA, kOhm, MOhm, nF, ...) |
14 | Carriage return (13/0x0d) |
Example packets:
01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 | 12 | 13 | 14 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
D | C | - | 0 | 0 | 0 | . | 0 | V | \r | ||||
A | C | 0 | 0 | . | 0 | 0 | A | \r | |||||
C | A | 0 | . | 0 | 7 | 1 | n | F | \r | ||||
O | H | O | . | L | M | O | h | m | \r |
Resources
- Original English vendor manual (2008)
- elv.de: Download zu: Digital-Multimeter MAS-345 (68-04 59 88):
- German manual from ELV (2002)
- "DMM VIEW" software, version 2.0 (for Win98/NT/ME/2000/XP; supports MAS343, MAS344, MAS345, M9803R)
- cczwei-forum.de: C# software for reading DMM values
- Linux Magazin: E-Werke: Perl misst Stromverbrauch mit Multimeter
- mas-345/marsh: multimeter read and store
- digitaltrip.hu: Mastech MAS-345 digital multimeter Windows GUI (github)
- github: device-mas345-perl
- b-redemann.de Auslesen von Messgeräten mit RS232 Interface über USB
- tmon (uses a MASTECH MAS345)