User manual

H70.0.21.6C-01 Operating Manual GMH 3511 page 11 of 14
8 Output
The output can be used as serial interface (for USB 3100, USB 3100 N, GRS 3100 or GRS 3105
interface adapters) or as analog output (0-1V).
If none of both is needed, we suggest to switch the output off, because battery life then is extended.
8.1 Serial Interface
By means of the serial interface and a suitable electrically isolated interface adapter (USB 3100, USB 3100 N,
GRS 3100 or GRS 3105) the device can be connected to a computer for data transfer.
With the GRS 3105 up to 5 devices of the GMH3xxx- series can be connected to one interface (see also
manual of GRS 3105). As a precondition the base addresses of all devices must not be identical, make sure to
configure the base addresses accordingly (refer menu point “Adr.” in chapter 7).
To avoid transmission errors, there are several security checks implemented e.g. CRC.
The following standard software packages are available:
 GSOFT3050: Operation and read out of logger function, data display in diagrams and tables
 GMHKonfig: Software for a comfortable editing of the device
 EBS 20M / 60M: 20-/60-channel software to display the measuring values
In case you want to develop your own software we offer a GMH3000-development package including:
 a universally applicable Windows functions library ('GMH3000.DLL') with documentation that can be used
by the most programming languages. Suitable for Windows XP™, Windows Vista™, Windows 7™
 Programming examples Visual Basic 4.0™, Delphi 1.0™, Testpoint™
The device has 2 channels:
- Channel 1: actual-value-channel pH, mV or rH and base address
- Channel 2: temperature value
The unit of all transmitter values (including measuring / boundary values) is the unit of
corresponding displayed values.
(e.g. temperature is displayed in °C -> temperature value is also transmitted in °C)
8.2 Analog output
An analog voltage 0-1 V can be connected at the universal output connector (mode: “Out dAC”).
The analog output cannot be scaled.
Unit 0V output signal 1V output signal
pH 0.00 pH 14.00 pH
mV / mV
H
-2000 mV 2000 mV
Please take care not to load the analog output too heavily, otherwise the output value will be distorted and
the power consumption will rise. Loads up to approx. 10 kOhm are unproblematic.
If the displayed value goes beyond the fixed value, the output voltage will be 1 V.
If the displayed value falls below the fixed value, the output voltage will be 0 V.
In error case (Err.1, Err.2, etc.) the output voltage will be slightly higher than 1 V.
plug wiring:
GND
+Uout
Attention!
The 3
rd
contact has to be left floating!
Only stereo plugs are allowed!
9 Accuracy Check / Adjustment Service
You can send the device to the manufacturer for adjustment and inspection.
Calibration certificate - DKD certificate - official certifications:
If the measuring instrument is supposed to receive a calibration certificate, it has to be sent to the
manufacturer (declare test levels, e.g. -20; 0°C; 70°C).
If the device is certificated together with a suitable sensor very high overall accuracies are possible.
Basic settings can only be checked and – if necessary – corrected by the manufacturer.
A calibration protocol is enclosed to the device ex works. This documents the precision reached by the
production process.