19
O&M Manual
Rev F (8/17)
Part 4 – Electrical Installation
4.1 General
The Q46 is powered in one of two ways, depending on the version purchased. The 12-24 VDC
powered analyzer requires a customer supplied DC power supply. The 90-260 VAC version
requires line power. Please verify the type of unit before connecting any power.
WARNING: Do not connect AC line power to a DC powered unit. Severe damage will
result.
Important Notes:
1. Use wiring practices that conform to all national, state and local electrical codes.
For proper safety as well as stable measuring performance, it is important that the
earth ground connection be made to a solid ground point from TB7. The AC power
supply contains a single 630mA slo-blo fuse (Wickmann/Littlefuse #372-0630). The
fuse F1 is located adjacent to TB7 and is easily replaceable.
2. Do NOT run sensor cables or instrument 4-20 mA output wiring in the same
conduit that contains AC power wiring. AC power wiring should be run in a
dedicated conduit to prevent electrical noise from coupling with the instrumentation
signals.
3. This analyzer must be installed by specifically trained personnel in accordance with
relevant local codes and instructions contained in this operating manual. Observe
the analyzer's technical specifications and input ratings. Proper electrical
disconnection means must be provided prior to the electrical power connected to
this instrument, such as a circuit breaker - rated 250 VAC, 2 A minimum. If one
line of the line power mains is not neutral, use a double-pole mains switch to
disconnect the analyzer.
4. Repeated problems with lightning strikes damaging sensitive instrumentation are
often attributed to poorly bonded earth grounds in the instrument power source. The
protection schemes incorporated into this analyzer cannot operate to maximum
efficiency unless the ground connection is at its’ absolute lowest impedance.
There is no standard ground resistance universally recognized. Many agencies
recommend a ground resistance value of 5 ohms or less. The NEC recommends an
impedance to ground of less than 25 ohms, and less than 5 ohms where sensitive
equipment is installed. Power sources feeding sensitive instruments like the
Q46H/79PR should have the lowest possible impedance to ground.
4.2 Power Connection
Verify the AC power supply requirement before installing. Also verify that power is fully
disconnected before attempting to wire.
Q46 systems are supplied with 5 cable gland fittings for sealing cable entries.
Connect HOT, NEUTRAL, and GROUND to the matching designations on terminal strip TB7.
To Next Page
Loading...