6.3 Static Test
If improper operation of the meter is suspected, the following resistance measurements can be made
to establish whether an electrical malfunction has occurred. An analog multimeter is required for
checking the electrodes. Either an analog or digital multimeter can be used for checking the coils.
These measurements can be made at the flowmeter pc board.
WARNING
Equipment that operates from ac line voltage constitutes a potential
electric shock hazard to the user. Make certain that the system power is
disconnected before making the following ohmmeter checks.
6.3.1 Magnet Coil Check
6.3.1.1 Signal Converter
Verify that the system power service has been de-energized. Turn off the power to the signal
converter to de-energize the meter. Remove cable leads M1 and M2/M3 from the customer terminal
block. Measure magnet coil series resistance by connecting the ohmmeter between M1 and M2/M3.
The value displayed should correspond to that indicated in Table 6-1. A reading of infinity or a short
circuit between leads indicates defective coil(s). If proper coil resistance is verified, reconnect cable
leads to terminals M1 and M2/M3. If coil(s) is defective, meter must be returned to the factory for
service.
TABLE 6 -1. METER COIL RESISTANCE
Meter Size
Coil Resistance
Nominal, ohms ±20%
inches mm
Each
Coil
Series
Resistance *
125156312
1
1
⁄
2
40 240 480
250190380
380110220
4 100 74 148
6 150 11 22
8 200 10.7 21.4
10 250 10.7 21.4
12 300 10.7 21.4
* M1 to M3
Reference temperature = 60
o
C
10DS3111E INSTRUCTION MANUAL
6-3
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